UVA 11078 Open Credit System(空间优化+时间优化)

//
//  main.cpp
//  Richard
//
//  Created by 邵金杰 on 16/9/30.
//  Mail:1016427040@qq.com or jasonshaosjj@gmail.com
//  Copyright © 2016年 邵金杰. All rights reserved.
//

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
int n;
scanf("%d",&n);
int x,ans,maxv;
scanf("%d",&x);
ans=-99999999;
maxv=x;
for(int i=1;i<n;i++){
scanf("%d",&x);
ans=max(ans,maxv-x);
maxv=max(maxv,x);
}
printf("%d\n",ans);
}
return 0;
}