PAT甲级 1001. A+B Format (20)--两种方法

题目链接：https://www.patest.cn/contests/pat-a-practise/1001

1001. A+B Format (20)

时间限制

400 ms

内存限制

65536 kB

代码长度限制

16000 B

判题程序

Standard

作者

CHEN, Yue

Calculate a + b and output the sum in standard format -- that is, the digits must be separated into groups of three by commas (unless there are less than four digits).

Input

Each input file contains one test case. Each case contains a pair of integers a and b where -1000000 <= a, b <= 1000000. The numbers are separated by a space.

Output

For each test case, you should output the sum of a and b in one line. The sum must be written in the standard format.

Sample Input

-1000000 9

Sample Output

-999,991

方法一：

通用方法。把两数和作为字符串处理。

#include
#include
#include
#include
using namespace std;
int main(){
    int a,b;
    cin>>a>>b;
    int c=a+b;
    if(c<0) cout<<'-';
    c=abs(c);
    char s[20];
    sprintf(s,"%d",c);
    int len=strlen(s);
    //if(len<=3) {cout<方法二： 
  
 
  
针对本题最多七位数的情况，写个特别的。
 
  
 
  
#include
#include
using namespace std;
int main(){
    int a,b;
    cin>>a>>b;
    int c=a+b;
    if(c<0){cout<<'-';c=-c;}
    if(c>=1000000){
        printf("%d,%03d,%03d",c/1000000,c%1000000/1000,c%1000);
    }else if(c>=1000){
        printf("%d,%03d",c/1000,c%1000);
    }else{
        printf("%d",c);
    }
    return 0;
}