完整简单c语言程序代码,初学C语言常用简单程序代码
帮助初学C语言的朋友
素数的筛选
#include
#include
#define N 1000
int main(int argc, char* argv[])
{
int i,j,num[N];
for(i=0;i
num[i]=i+1;
for(i=1;i
{
if(num[i])
{
for(j=i+1;j
{
if(num[j])
if(num[j]%num[i]==0)
num[j]=0;
}
}
}
for(i=1;i
if(num[i])
printf(" %d",num[i]);
return 0;
}
输出时分秒
#include
main()
{
int x,s,t,d;
scanf("%d",&x);
s=x%60;
t=(x/60)%60;
d=(x/60)/60;
printf("%d时%d分%d秒",d,t,s);
}
三个数的交换
#include
void main()
{
int a,b,c,t;
scanf("%d%d%d",&a,&b,&c);
printf("The original number:a=%d,b=%d,c=%d\n",a,b,c);
t=a,a=b,b=t;
t=a,a=c,c=t;
printf("after swap:a=%d,b=%d,c=%d",a,b,c);
}
switch语句的运用
#include
main()
{
int a,m;
printf("please input a number:");
scanf("%d",&a);
switch(a/10)
{
case 10:
case 9: m=5; break;
case 8: m=4; break;
case 7:m=3; break;
case 6:m=2; break;
default:m=1;
}
printf("m=%d",m);
}
判断奇数和偶数
#include
main()
{
int x;
printf("Please input a number: ");
scanf("%d",&x);
if(x%2==0)
printf("this is a oushu!");
else
printf("this is a jishu!");
}
小写改大写，若是大写则不变
include
main()
{
char c1,c2;
printf("Input a letter\n");
scanf("%c",&c1);
c2=('a'<=c1&&c1<='z')?(c1-'a'+'A'):c1;
printf("%c",c2);
getchar();
return 0;
}
输入一个数，输出这个数是几位数
#include
main()
{
int x,n;
printf("please input a number:");
scanf("%d",&x);
n=0;
while(x!=0)
{
x=x/10;
n++;
}
printf("%d",n);
}
输入一个数，判断它是几位数，然后逆序输出
#include
int main()
{
int num;
int len = 0;
int temp =0;
printf("Please input a number:\n");
scanf("%d",&num);
while((num % 10)!=0)
{
temp = temp*10+(num%10);
len++;
num = num/10;
}
printf("length = %d\n",len);
printf("Reverse is %d", temp);
}
打印水仙花数
#include
main()
{
int x, a,b,c;
for(x=100;x<=999;x++)
{
a=x%10;
b=(x/10)%10;
c=x/100;
if(x==a*a*a+b*b*b+c*c*c)
{
printf("%5d",x);
}
}
printf("\n");
}
判断闰年
#include "stdio.h"
main()
{
int k,flag,n=0;
for(k=1980;k<=2880;k++)
{
flag=(k%4==0)&&(k%100!=0)||(k%400==0);
if(flag)
{ printf("%5d",k);
n++;
if(n%10==0)
printf("\n");
}
}
printf("\n");
}
求1-3+5-7...-99+101的值
#include
main()
{
int sum,i,t;
sum=1;
t=1;
for(i=3;i<=101;i=i+2)
{
t=-t;
sum=sum+t*i;
}
printf("sum=%d",sum);
}
求前n项和
#include
main()
{
float s,t;
int n,i,fz,fm;
s=0;
fz=2;
fm=1;
printf("Enter n:");
scanf("%d",&n);
for(i=1;i<=n;i++)
{