可能没有考虑到所有情况,但基本的计算可以做到!
Calculator.h
#pragma once
#include
#include "ui_Calculator.h"
#include "calculation.h"
#include
#include
#include
#include
const int TOTALNUM = 10; // 数字键总数
const int OPERATORNUM = 6; // 操作符总数
const int WIDTH = 300; // 默认窗口宽度
const int HEIGHT = 450; // 默认窗口高度
const int ZOOMINWIDTH = 600; // 显示历史记录栏时的窗口宽度
const int BUTTONWIDTH = 60; // 按钮的宽度
const int BUTTONHEIGHT = 40; // 按钮的高度
const int SMALLBUTTONWIDTH = 30; // 小图标的宽度
const int SMALLBUTTONHEIGHT = 30; // 小图标的高度
class Calculator : public QDialog
{
Q_OBJECT
public:
Calculator(QWidget *parent = Q_NULLPTR);
private:
Ui::CalculatorClass ui;
private:
calculation c;
QPushButton *histotyButton;
QPushButton *numButton[TOTALNUM];
QPushButton *operatorButton[OPERATORNUM];
QPushButton *pointButton;
QPushButton *leftParenthesesButton;
QPushButton *rightParenthesesButton;
QPushButton *sinButton;
QPushButton *cosButton;
QPushButton *tanButton;
QPushButton *sqrtButton;
QPushButton *squareButton;
QPushButton *logButton;
QPushButton *expButton;
QPushButton *none1;
QPushButton *none2;
QPushButton *miciButton;
QPushButton *tenMiciButton;
QPushButton *factorialButton;
QPushButton *positiveAndNegativeButton;
QPushButton *piButton;
QPushButton *clearButton;
QPushButton *backspaceButton;
QLineEdit *expressionLineEdit;
QPlainTextEdit *historyResultTextEdit;
private:
void initButton();
void setButton(QPushButton * button, const QString & filePath, const int & width, const int & height, const int & buttonWidth = BUTTONWIDTH, const int & buttonHeight = BUTTONHEIGHT);
void initLineEdit();
char* getLastNum();
private slots:
void onNumButtonClicked(const qreal & num);
void onOperatorButtonClicked(const char & operatorName);
void backspaceButtonClicked();
void clearButtonClicked();
void triFunButtonClicked(const QString & tri);
void squareButtonClicked();
void sqrtButtonClicked();
void powButtonClicked();
void tenPowButtonClicked();
void positiveAndNegativeButtonClicked();
void eFunButtonClicked(const QString & e);
void histotyButtonClicked();
};
Calculaor.cpp
#include "Calculator.h"
bool zoomin = false; // 是否放大(显示历史栏)
const char OPERATOR[] = "%/*-+=";
Calculator::Calculator(QWidget *parent)
: QDialog(parent)
{
ui.setupUi(this);
// 初始化
initButton();
initLineEdit();
}
// 简单计算阶乘
double factorial(int n) {
double res = 1;
while (n > 0) {
res *= n;
n--;
}
return res;
}
void Calculator::initButton()
{
setMinimumSize(WIDTH, HEIGHT);
setMaximumSize(WIDTH, HEIGHT);
QString iconPath;
int j = 1;
int i;
// 初始化数字按钮
for (i = 0; i < TOTALNUM; ++i) {
numButton[i] = new QPushButton(this);
iconPath = "./img/num" + QString::number(i) + ".png";
if (i == 0) {
setButton(numButton[i], iconPath, (WIDTH - BUTTONWIDTH) >> 1, HEIGHT - BUTTONHEIGHT);
}
else {
if (i % 3 == 1) {
j++;
}
setButton(numButton[i], iconPath, BUTTONWIDTH * ((i - 1) % 3 + 1), HEIGHT - j * BUTTONHEIGHT);
}
// 通过lamda表达式进行传参
connect(numButton[i], &QPushButton::clicked, this, [=] {onNumButtonClicked(i); });
}
// 初始化加 减 乘 除 取余 等于
for (i = 0; i < OPERATORNUM; ++i) {
operatorButton[i] = new QPushButton(this);
iconPath = "./img/operator" + QString::number(i + 1) + ".png";
setButton(operatorButton[i], iconPath, WIDTH - BUTTONWIDTH, HEIGHT - BUTTONHEIGHT * (OPERATORNUM - i));
connect(operatorButton[i], &QPushButton::clicked, this, [=] {onOperatorButtonClicked(OPERATOR[i]); });
}
// 初始化小数点按钮
pointButton = new QPushButton(this);
setButton(pointButton, "./img/point.png", WIDTH - BUTTONWIDTH * 2, HEIGHT - BUTTONHEIGHT);
connect(pointButton, &QPushButton::clicked, this, [=] {onOperatorButtonClicked('.'); });
// 初始化左括号按钮
leftParenthesesButton = new QPushButton(this);
setButton(leftParenthesesButton, "./img/leftParentheses.png", 0, HEIGHT - BUTTONHEIGHT);
connect(leftParenthesesButton, &QPushButton::clicked, this, [=] {onOperatorButtonClicked('('); });
// 初始化右括号按钮
rightParenthesesButton = new QPushButton(this);
setButton(rightParenthesesButton, "./img/rightParentheses.png", BUTTONWIDTH, HEIGHT - BUTTONHEIGHT);
connect(rightParenthesesButton, &QPushButton::clicked, this, [=] {onOperatorButtonClicked(')'); });
// 初始化三角函数按钮
sinButton = new QPushButton(this);
cosButton = new QPushButton(this);
tanButton = new QPushButton(this);
setButton(sinButton, "./img/sin.png", WIDTH - 3 * BUTTONWIDTH, HEIGHT - 7 * BUTTONHEIGHT);
setButton(cosButton, "./img/cos.png", WIDTH - 2 * BUTTONWIDTH, HEIGHT - 7 * BUTTONHEIGHT);
setButton(tanButton, "./img/tan.png", WIDTH - BUTTONWIDTH, HEIGHT - 7 * BUTTONHEIGHT);
connect(sinButton, &QPushButton::clicked, this, [=] {triFunButtonClicked("sin"); });
connect(cosButton, &QPushButton::clicked, this, [=] {triFunButtonClicked("cos"); });
connect(tanButton, &QPushButton::clicked, this, [=] {triFunButtonClicked("tan"); });
// 初始化开方与开根号
sqrtButton = new QPushButton(this);
squareButton = new QPushButton(this);
setButton(sqrtButton, "./img/sqrt.png", 0, HEIGHT - 6 * BUTTONHEIGHT);
setButton(squareButton, "./img/square.png", 0, HEIGHT - 7 * BUTTONHEIGHT);
connect(sqrtButton, SIGNAL(clicked()), this, SLOT(sqrtButtonClicked()));
connect(squareButton, SIGNAL(clicked()), this, SLOT(squareButtonClicked()));
// 初始化对数函数与指数函数按钮
logButton = new QPushButton(this);
expButton = new QPushButton(this);
setButton(logButton, "./img/log.png", WIDTH - 3 * BUTTONWIDTH, HEIGHT - 6 * BUTTONHEIGHT);
setButton(expButton, "./img/exp.png", WIDTH - 2 * BUTTONWIDTH, HEIGHT - 6 * BUTTONHEIGHT);
connect(logButton, &QPushButton::clicked, this, [=] {eFunButtonClicked("log"); });
connect(expButton, &QPushButton::clicked, this, [=] {eFunButtonClicked("exp"); });
// 初始化暂无用处的按钮
none1 = new QPushButton(this);
none2 = new QPushButton(this);
setButton(none1, "./img/none1.png", 0, HEIGHT - 5 * BUTTONHEIGHT);
setButton(none2, "./img/none2.png", BUTTONWIDTH, HEIGHT - 5 * BUTTONHEIGHT);
// 初始化幂次按钮
miciButton = new QPushButton(this);
tenMiciButton = new QPushButton(this);
setButton(miciButton, "./img/mici.png", BUTTONWIDTH, HEIGHT - 7 * BUTTONHEIGHT);
setButton(tenMiciButton, "./img/tenMici.png", BUTTONWIDTH, HEIGHT - 6 * BUTTONHEIGHT);
connect(miciButton, SIGNAL(clicked()), this, SLOT(powButtonClicked()));
connect(tenMiciButton, SIGNAL(clicked()), this, SLOT(tenPowButtonClicked()));
// 初始化阶乘按钮
factorialButton = new QPushButton(this);
setButton(factorialButton, "./img/factorial.png", 0, HEIGHT - 3 * BUTTONHEIGHT);
connect(factorialButton, &QPushButton::clicked, this, [=] {onOperatorButtonClicked('!'); });
// 初始化切换正负号的按钮
positiveAndNegativeButton = new QPushButton(this);
setButton(positiveAndNegativeButton, "./img/positiveAndNegative.png", 0, HEIGHT - 2 * BUTTONHEIGHT);
connect(positiveAndNegativeButton, SIGNAL(clicked()), this, SLOT(positiveAndNegativeButtonClicked()));
// 初始化PI按钮
piButton = new QPushButton(this);
setButton(piButton, "./img/pi.png", 0, HEIGHT - 4 * BUTTONHEIGHT);
connect(piButton, &QPushButton::clicked, this, [=] {onNumButtonClicked(3.14); });
// 初始化清屏按钮
clearButton = new QPushButton(this);
setButton(clearButton, "./img/clear.png", WIDTH - 3 * BUTTONWIDTH, HEIGHT - 5 * BUTTONHEIGHT);
connect(clearButton, SIGNAL(clicked()), this, SLOT(clearButtonClicked()));
// 初始化退格按钮
backspaceButton = new QPushButton(this);
setButton(backspaceButton, "./img/backspace.png", WIDTH - 2 * BUTTONWIDTH, HEIGHT - 5 * BUTTONHEIGHT);
connect(backspaceButton, SIGNAL(clicked()), this, SLOT(backspaceButtonClicked()));
// 初始化显示历史记录按钮
histotyButton = new QPushButton(this);
setButton(histotyButton, "./img/history.png", 0, 0, SMALLBUTTONWIDTH, SMALLBUTTONHEIGHT);
connect(histotyButton, SIGNAL(clicked()), this, SLOT(histotyButtonClicked()));
}
// 设置按钮
// 后面两个参数默认是 BUTTONWIDTH(60) 和 BUTTONHEIGHT(40)
void Calculator::setButton(QPushButton * button, const QString & filePath
, const int & width, const int & height
, const int & buttonWidth, const int & buttonHeight)
{
button->setGeometry(width, height, buttonWidth, buttonHeight);
button->setIcon(QIcon(filePath));
button->setIconSize(QSize(buttonWidth, buttonHeight));
}
// 初始化答案栏和历史记录栏
void Calculator::initLineEdit()
{
expressionLineEdit = new QLineEdit(this);
expressionLineEdit->setGeometry(0, HEIGHT - 9 * BUTTONHEIGHT, WIDTH, BUTTONHEIGHT);
expressionLineEdit->setFont(QFont("微软雅黑", 24)); // 设置字体
expressionLineEdit->setReadOnly(true); // 无法用键盘修改
historyResultTextEdit = new QPlainTextEdit(this);
historyResultTextEdit->setGeometry(WIDTH, 0, ZOOMINWIDTH - WIDTH, HEIGHT);
historyResultTextEdit->setFont(QFont("微软雅黑", 24)); // 设置字体
historyResultTextEdit->setReadOnly(true); // 无法用键盘修改
}
// 找到最后一个数字(对于某些特殊函数需要这个操作)
char* Calculator::getLastNum()
{
std::string s = expressionLineEdit->text().toStdString();
size_t length = strlen(s.c_str());
char res[NUMSIZE];
memset(res, '\0', NUMSIZE);
/*
*判断条件:
*当前位不是操作符
*或者 当前位为操作符(+,-)且前面为e
*或者 当前操作符是负号并且负号前面也是操作符
*/
for (int i = length - 1; i >= 0
&& (!c.isOperator(s[i])
|| (c.isOperator(s[i]) && (0 == i || 'e' == s[i - 1]))
|| ('-' == s[i] && (i == 0 || c.isOperator(s[i - 1])))); --i) {
strcpy(res, strcat(ctocstar(s[i]), res));
expressionLineEdit->backspace();
}
return res;
}
// 设置按钮槽函数
void Calculator::onNumButtonClicked(const qreal & num)
{
std::string tempStr = expressionLineEdit->text().toStdString();
// PI进行特殊处理
// 如果不为空,且PI前面是操作符就加个乘号
if (3.14 == num && "" != tempStr
&& (!c.isOperator(tempStr.back())
|| ')' == tempStr.back())) {
expressionLineEdit->setText(expressionLineEdit->text() + '*' + QString::number(num));
}
else {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(num));
}
}
void Calculator::onOperatorButtonClicked(const char & operatorName)
{
std::string tempStr = expressionLineEdit->text().toStdString();
/*
*等于号需要单独判断
*如果为空则不进行计算
*如果最后一位是操作符也不进行计算
*如果计算有误则清空
*/
if ('=' == operatorName) {
if ("" == expressionLineEdit->text()) {
QMessageBox::information(NULL, "warning!", "you can't do this!");
return;
}
if (c.isOperator(tempStr.back())) {
if (')' != tempStr.back()) {
QMessageBox::information(NULL, "warning!", "you can't put a single operator at the end!");
return;
}
}
double res = c.calculate(tempStr.c_str());
if (WRONGTAG == res) {
expressionLineEdit->clear();
}
else {
historyResultTextEdit->setPlainText(expressionLineEdit->text()
+ '='
+ QString::number(res)
+ '\n'
+ historyResultTextEdit->toPlainText());
expressionLineEdit->setText(QString::number(res));
}
}
// 单独处理阶乘符号
else if ('!' == operatorName) {
char* res = new char[NUMSIZE];
strcpy(res, getLastNum());
double d = c.stod(res);
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(factorial(d)));
}
// 单独处理小数点符号
else if ('.' == operatorName) {
if ("" != tempStr && !c.isOperator(tempStr.back()) && '.' != tempStr.back()) {
expressionLineEdit->setText(expressionLineEdit->text() + '.');
}
}
/*
*为空只能放左括号或者负号
*左括号前面是数字就补乘号
*前面不能是操作符(除了')')
*/
else if ('(' == operatorName) {
if ("" != expressionLineEdit->text() && !c.isOperator(tempStr.back())) {
expressionLineEdit->setText(expressionLineEdit->text() + '*');
}
expressionLineEdit->setText(expressionLineEdit->text() + operatorName);
}
else if ("" == expressionLineEdit->text() && '-' == operatorName) {
expressionLineEdit->setText(expressionLineEdit->text() + operatorName);
}
else if(("" != expressionLineEdit->text()
&& (!c.isOperator(tempStr.back()) && '.' != tempStr.back() || ')' == tempStr.back()))){
expressionLineEdit->setText(expressionLineEdit->text() + operatorName);
}
}
void Calculator::backspaceButtonClicked()
{
expressionLineEdit->backspace();
}
void Calculator::clearButtonClicked()
{
expressionLineEdit->clear();
}
void Calculator::triFunButtonClicked(const QString & tri)
{
char* res = new char[NUMSIZE];
strcpy(res, getLastNum());
double d = c.stod(res);
if ("sin" == tri) {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(sin(d)));
}
else if ("cos" == tri) {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(cos(d)));
}
else if ("tan" == tri) {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(tan(d)));
}
}
void Calculator::squareButtonClicked()
{
char* res = new char[NUMSIZE];
strcpy(res, getLastNum());
double d = c.stod(res);
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(pow(d, 2)));
}
void Calculator::sqrtButtonClicked()
{
char* res = new char[NUMSIZE];
strcpy(res, getLastNum());
double d = c.stod(res);
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(pow(d, 0.5)));
}
void Calculator::powButtonClicked()
{
expressionLineEdit->setText(expressionLineEdit->text() + "^");
}
void Calculator::tenPowButtonClicked()
{
std::string tempStr = expressionLineEdit->text().toStdString();
// 处理方式同PI
if ("" != tempStr && (!c.isOperator(tempStr.back())
|| ')' == tempStr.back())) {
expressionLineEdit->setText(expressionLineEdit->text() + '*');
}
expressionLineEdit->setText(expressionLineEdit->text() + "10^");
}
void Calculator::positiveAndNegativeButtonClicked()
{
// do nothing
}
void Calculator::eFunButtonClicked(const QString & e)
{
char* res = new char[NUMSIZE];
strcpy(res, getLastNum());
double d = c.stod(res);
if ("exp" == e) {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(exp(d)));
}
else if ("log" == e) {
if (d <= 0) {
QMessageBox::information(NULL, "warning!", "you can't use this number as the base");
expressionLineEdit->clear();
}
else {
expressionLineEdit->setText(expressionLineEdit->text() + QString::number(log(d)));
}
}
}
void Calculator::histotyButtonClicked()
{
if (false == zoomin) {
setMinimumSize(ZOOMINWIDTH, HEIGHT);
setMaximumSize(ZOOMINWIDTH, HEIGHT);
zoomin = true;
}
else if (true == zoomin) {
setMinimumSize(WIDTH, HEIGHT);
setMaximumSize(WIDTH, HEIGHT);
zoomin = false;
}
}
calculation.h
#pragma once
#include "vector.h"
#include "stack.h"
#include
const int NUMSIZE = 20; // 设置数组的缓冲长度
const int WRONGTAG = -INT_MAX; // 错误标记
class calculation {
public:
double stod(char* s);
bool isOperator(const char c);
double calculate(const char* expressions);
};
char* ctocstar(char c);
calculation.cpp
#pragma warning(disable:4996)
#include "calculation.h"
const char* operators = "+-*/%()^";
// 栈外优先数
int icp(const char c)
{
switch (c)
{
case '(':return 6;
case '*':
case '/':
case '^':
case '%':return 4;
case '+':
case '-':return 2;
case ')':return 1;
default:break;
}
return 0;
}
// 栈内优先数
int isp(const char c)
{
switch (c)
{
case '(':return 1;
case '*':
case '/':
case '^':
case '%':return 5;
case '+':
case '-':return 3;
case ')':return 6;
default:break;
}
return 0;
}
// 将字符串转换成数字
double calculation::stod(char * s)
{
double res = 0;
bool isNegative = s[0] == '-' ? true : false; // 判断是否为负数
int i = 0;
int size = 0; // 数字长度(在e之前)
int ePos = -1; // 找到e的位置,如果没有找到则是-1
int pointPos = -1; // 找到小数点的位置,如果没有找到则是-1
for (i = isNegative; s[i] != '\0'; ++i) {
if (s[i] == '.') {
pointPos = i;
size++;
}
else if (s[i] == 'e') {
ePos = i;
break;
}
else {
size++;
}
}
// 计算结果
for (i = isNegative; i < size + isNegative; ++i) {
if (i == pointPos) {
continue;
}
res = res * 10 + (s[i] - '0');
}
if (-1 != pointPos) {
while (size != pointPos + 1) {
res = res / 10;
size--;
}
}
// 处理指数部分
if (-1 != ePos) {
int exponential = 0; // 指数部分
bool isNegativeExp = s[ePos + 1] == '-' ? true : false; // 判断指数部分是否为负数
for (i = ePos + 2; s[i] != '\0'; ++i) {
exponential = exponential * 10 + (s[i] - '0');
}
if (isNegativeExp) {
while (exponential--) {
res /= 10;
}
}
else {
while (exponential--) {
res *= 10;
}
}
}
return isNegative ? -res : res;
}
bool calculation::isOperator(const char c)
{
for (int i = 0; operators[i] != '\0'; ++i) {
if (c == operators[i]) {
return true;
}
}
return false;
}
char* ctocstar(const char c) {
char *ch = new char[2];
ch[0] = c;
ch[1] = '\0';
return ch;
}
double calculation::calculate(const char * expressions)
{
if ("" == expressions) {
return WRONGTAG;
}
Stack numStack; // 储存数字的栈
Stack symStack; // 储存符号的栈
// 将中缀表达式转换成后缀表达式
char num[NUMSIZE]; // 用于解析表达式中的数字
sprintf_s(num, NUMSIZE, "%c", '\0');
char temp = NULL;
Vector sufExpressions;
int i = NULL;
for (i = 0; expressions[i] != '\0'; ++i) {
temp = expressions[i];
// 如果不是操作符就加到num内
// 加减号前面是e要进行处理
if (!isOperator(temp) || (isOperator(temp) && expressions[i - 1] == 'e')) {
sprintf_s(num, NUMSIZE, "%s%c", num, temp);
}
// 如果是操作符
else {
char *tempch = new char[NUMSIZE];
strcpy(tempch, num);
if (num[0] != '\0') {
sufExpressions.push_back(tempch); // 将数字输出到后缀表达式中
}
sprintf_s(num, NUMSIZE, "%c", '\0');
/*
*如果栈为空则直接压栈
*如果不为空则比较栈外元素与栈内元素大小
*如果栈外操作符大于栈内操作符,入栈
*反之则输出到后缀表达式中,然后循环
*/
if (')' == temp) {
// 如果是右括号则一直输出到后缀表达式中,直至碰到左括号
while (!symStack.empty() && symStack.top() != '(') {
sufExpressions.push_back(ctocstar(symStack.top()));
symStack.pop();
}
// 如果为空则说明没有匹配的左括号
if (symStack.empty()) {
QMessageBox::information(NULL, "warning!", "lack of leftparentheses!");
return WRONGTAG;
}
else {
// 将左括号弹出
symStack.pop();
}
}
else {
while (!symStack.empty() && (isp(symStack.top()) > icp(temp))) {
sufExpressions.push_back(ctocstar(symStack.top()));
symStack.pop();
}
symStack.push(temp);
}
}
}
// 处理最后一位数字
if (num[0] != '\0') {
sufExpressions.push_back(num);
}
// 将栈内剩余操作符输出
while (!symStack.empty()) {
sufExpressions.push_back(ctocstar(symStack.top()));
symStack.pop();
}
double tempNum1 = NULL, tempNum2 = NULL;
// 计算后缀表达式
for (i = 0; i < sufExpressions.size(); ++i) {
if (0 == strcmp(sufExpressions[i], "+")) {
tempNum1 = numStack.top();
numStack.pop();
tempNum2 = numStack.top();
numStack.pop();
numStack.push(tempNum1 + tempNum2);
}
else if (0 == strcmp(sufExpressions[i], "-")) {
tempNum1 = numStack.top();
numStack.pop();
// 如果数字栈为空或者负号在最后则直接取反(单目运算)
if (numStack.empty() || (i < sufExpressions.size() - 1 && isOperator(sufExpressions[i + 1][0]))) {
tempNum2 = 0;
}
else {
tempNum2 = numStack.top();
numStack.pop();
}
numStack.push(tempNum2 - tempNum1);
}
else if (0 == strcmp(sufExpressions[i], "*")) {
tempNum1 = numStack.top();
numStack.pop();
tempNum2 = numStack.top();
numStack.pop();
numStack.push(tempNum1 * tempNum2);
}
else if (0 == strcmp(sufExpressions[i], "/")) {
tempNum1 = numStack.top();
numStack.pop();
tempNum2 = numStack.top();
numStack.pop();
// 除数不能为0
if (tempNum1 == 0) {
QMessageBox::information(NULL, "warning!", "you can't divide zero!");
return WRONGTAG;
}
else {
numStack.push(tempNum2 / tempNum1);
}
}
else if (0 == strcmp(sufExpressions[i], "%")) {
tempNum1 = numStack.top();
numStack.pop();
tempNum2 = numStack.top();
numStack.pop();
// 如果被除数小于0要进行处理
if (tempNum2 < 0) {
numStack.push(tempNum1 + (tempNum2 - (int)(tempNum2 / tempNum1) * tempNum1));
}
else {
numStack.push(tempNum2 - (int)(tempNum2 / tempNum1) * tempNum1);
}
}
else if (0 == strcmp(sufExpressions[i], "^")) {
tempNum1 = numStack.top();
numStack.pop();
tempNum2 = numStack.top();
numStack.pop();
numStack.push(pow(tempNum2, tempNum1));
}
else if (0 == strcmp(sufExpressions[i], "(")) {
QMessageBox::information(NULL, "warning!", "lack of rightparenteses!");
return WRONGTAG;
}
else {
numStack.push(stod(sufExpressions[i]));
}
}
// 如果结果栈为空则返回0
if (numStack.empty()) {
return 0;
}
return numStack.top();
}
链接:https://share.weiyun.com/5A45cgb
图片的素材在链接里面,是微软计算器的截图