C++-HDU1000,1001,1002-格式是真的坑

#include <cstdio>
int main(){
    for(int a,b;~scanf("%d%d",&a,&b);printf("%d
",a+b));
    return 0;
}

#include <cstdio>
int main(){
    for(int n;scanf("%d",&n)!=EOF;printf("%d

",(n%2==0?((n/2)*(1+n)):((1+n)/2)*n)));
    return 0;
}

#include <cmath>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
int main() {
    char s1[1000],s2[1000],s3[1001];
    int num1[1000],num2[1000],num3[1001],t,T;
    for(scanf("%d",&T),t=1; t<=T; t++) {
        scanf("%s%s",s1,s2);
        memset(num1,0,sizeof(num1));
        memset(num2,0,sizeof(num2));
        memset(num3,0,sizeof(num3));
        memset(s3,0,sizeof(s3));
        int len1=strlen(s1),len2=strlen(s2),len3=max(len1,len2);
        for(int i=len1-1,cnt=0;i>=0;num1[cnt++]=s1[i]-'0',i--);
        for(int i=len2-1,cnt=0;i>=0;num2[cnt++]=s2[i]-'0',i--);
        for(int i=0;i<len3;i++)num3[i]=num1[i]+num2[i];
        for(int i=0;i<len3;i++)if(num3[i]>9)num3[i+1]++,num3[i]%=10;
        if(num3[len3])len3++;
        for(int i=len3-1,cnt=0; i>=0; i--) s3[cnt++]=num3[i]+'0';
        printf("Case %d:
%s + %s = %s
",t,s1,s2,s3);
        if(t!=T)printf("
");
    }
    return 0;
}