HDU 5878 I Count Two Three (打表+二分查找) -2016 ICPC 青岛赛区网络赛

#include <iostream>
#include <math.h>
#include <stdio.h>
#include<algorithm>
using namespace std;
long long data[1000000],tot=0;
int main()
{
    long long maxn = 1000000007;
    long long a,b,c,d;
    for(a=1;a<=maxn;a*=2)
    for(b=1;a*b<=maxn;b*=3)
    for(c=1;a*b*c<=maxn;c*=5)
    for(d=1;a*b*c*d<=maxn;d*=7){
        data[tot++] = a*b*c*d;
    }
    sort(data,data+tot);

    int t,n;
    scanf("%d",&t);
    while(t--) {
        scanf("%d",&n);
        int pos = upper_bound(data,data+tot,n)-data;
        if(pos>0&&data[pos-1]==n) pos--;
        printf("%lld\n",data[pos]);
    }
    return 0;
}