POJ 1064 Cable master 【二分答案】

和杭电那一题一样，只不过G++交不能通过，C++能过

wa了好多好多好多次-----------------------------------------

#include<iostream>  
#include<cstdio>  
#include<cstring> 
#include <cmath> 
#include<stack>
#include<vector>
#include<map> 
#include<set>
#include<queue> 
#include<algorithm>  
using namespace std;

typedef long long LL;
const int INF = (1<<30)-1;
const int mod=1000000007;
const int maxn=10005;
const int Exp=1e-6;

double a[maxn];
int n,k;

bool ok(double x){
    int ans=0;
    for(int i=0;i<n;i++){
        ans+=(int) (a[i]/x );
    }
    return ans>=k;
}

int main(){
    scanf("%d %d",&n,&k);
    for(int i=0;i<n;i++) scanf("%lf",&a[i]);
    
    double lb=0,ub= INF,mid;
    for(int i=0;i < 100;i++){
        mid=(lb + ub)/2;
        if(ok(mid)) lb=mid;
        else ub=mid;
        
    //    printf("lb=%lf
",lb);
    //    printf("ub=%lf
",ub);
    //    printf("mid=%lf
",mid);
    }
    printf("%.2lf
",(floor)(mid*100)/100);
    
    return 0;
}