【BZOJ】1257 余数之和

标签：余数   数论   高斯记号   代数变形   bzoj   

/**************************************************************
    Problem: 1257
    User: y20070316
    Language: C++
    Result: Accepted
    Time:8 ms
    Memory:804 kb
****************************************************************/
 
#include <cstdio>
#include <cstring>
#include <cstdlib>
using namespace std;
 
typedef long long LL;
 
int n,m;
LL sum;
 
int main(void)
{   
    scanf("%d%d",&n,&m);
     
    sum+=(LL)n*m;
    if (n>m) n=m;
     
    int l,r,j;
    for (int i=1;i<=n;i=r+1)
    {
        j=m/i,l=m/(j+1)+1,r=m/j;
        if (r>=n) r=n;
        sum-=(LL)(l+r)*(r-l+1)*j/2;
    }
    printf("%lld\n",sum);
     
    return 0;
}

【BZOJ】1257 余数之和

标签：余数   数论   高斯记号   代数变形   bzoj   

原文地址：http://blog.csdn.net/u013598409/article/details/47037031