XDOJ_1023_二分查找

Posted 2020-08-15

http://acm.xidian.edu.cn/problem.php?id=1023

 

因为区间不重复，所以就好办了。

把l和r、id分开保存，排序后下标还是对应的，偷懒直接用lowerbound解决。

 

#include<iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
using namespace std;

int f(int x)
{
    int now = 5,ans = 0;
    while(now <= x)
    {
        ans += x/now;
        now *= 5;
    }
    return ans;
}
int main()
{
    int T,n;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d",&n);
        int ans = n*4;
        while(f(ans) < n)    ans++;
        if(f(ans) == n)    printf("%d\n",ans);
        else    printf("No solution\n");
    }
    return 0;
}