1001 A+B Format C语言

@PAT 题库1001 A+B Format (20 分)

题目

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 Specification:

Each input file contains one test case. Each case contains a pair of integers a and b where −10^​6≤a b≤10^6. The numbers are separated by a space.

Output Specification:

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

代码如下：

#include <stdio.h>
#include <string.h>
char s[100];
int main() {
int a,b;
    while(scanf("%d%d",&a,&b)!=EOF){  
    a = a+b;
    if (a < 0) {
        putchar('-');
        a = -a;
    }
    sprintf(s,"%d",a);
    int n = strlen(s), m = n % 3,i = 0;
    for (; i < m; ++i) {
        putchar(s[i]);
    }
    for (; i < n; i += 3) {
        if (i) {
            putchar(',');
        }
        printf("%c%c%c",s[i],s[i + 1],s[i + 2]);
    }
    puts("");
    return 0;
    }
}

#include<stdio.h>
#include<string.h>
char s[100];
int main() {
int a,b,i;
  while(scanf("%d%d",&a,&b) != EOF){
    a=a+b;
    if(a<0){
        putchar('-');
        a=-a;
    }
    sprintf(s,"%d",a);
    int n=strlen(s);
    for(i=0;i<n;i++)
       {
            putchar(s[i]);
            if((n-i-1)%3==0 && n-i-1!=0 ) putchar(',');
       }
    return 0;
  }

} 

这一个没有编译警告。