PAT甲级1001水题飘过

#include<iostream>
using namespace std;

int main(){
    int a, b;
    while(scanf("%d%d", &a, &b) != EOF){
        int c = a + b;
        if(c == 0) printf("0\n");
        else{
            if(c < 0){
                printf("-");
                c = -c;
            }
            int k[5];
            int cnt = 0;
            while(c != 0){
                int x = c % 1000;
                c /= 1000;
                k[cnt++] = x;
            }
            for(int i = cnt-1; i >= 0; i--){
                if(i != cnt-1){
                    printf("%03d", k[i]);
                }else{
                    printf("%d", k[i]);
                }
                if(i != 0) printf(",");
            }
            printf("\n");
        }
    }
    return 0;
}