UVa 11059 Maximum Product

Code：

#include<stdio.h>

#include<stdlib.h>

#include<iostream>

#include<algorithm>

#include<string.h>

#include<map>

#include<vector>

using namespace std;

long long int arr[20];

int main()

{

    int n,cas=1;

    while(scanf("%d",&n)!=EOF)

    {

        long long int maxn=-1000000000;

        memset(arr,0,sizeof(arr));

        for(int i=0; i<n; i++) cin>>arr[i];

        if(n==1) maxn=arr[0];

        for(int i=0; i<n; i++)

        {

            maxn=max(maxn,arr[i]);

            for(int j=i+1; j<n; j++)

            {

                arr[i]*=arr[j];

                maxn=max(maxn,arr[i]);

            }

        }

        if(maxn<0) printf("Case #%d: The maximum product is 0.\n",cas++);

        else printf("Case #%d: The maximum product is %lld.\n",cas++,maxn);

        printf("\n");

    }

    return 0;

}