杭电acm 1001

#include<cstdio>
int main()
{
    int n;
    while(scanf("%d",&n)!=EOF)
    {
        if(n%2==0)
        printf("%d\n\n",n/2*(n+1));
        else
        printf("%d\n\n",(n+1)/2*n); 
    }
    return 0;
}

//通过

 

#include<cstdio>
int main()
{
    int n;
    while(scanf("%d",&n))
    {
        if(n%2==0)
        printf("%d\n\n",n/2*(n+1));
        else
        printf("%d\n\n",(n+1)/2*n); 
    }
    return 0;
}

//超时

区别： EOF

这道题主要考虑数据溢出！！！