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hdu 4699 Editor 模拟
多校10,1004 比赛的时候一直想构造个伸展树，结果写挫了。赛后发现其实就两个栈，顿时感觉被虐成渣了
/*
author:jxy
lang:C/C++
university:China,Xidian University
**If you need to reprint,please indicate the source**
*/
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <stack>
using namespace std;
stack<int> a,b;
int sum[1000005];
int Max[1000005];
int now;
int main()
{
int Q;
while(~scanf("%d",&Q))
{
while(!a.empty())a.pop();
while(!b.empty())b.pop();
int i,t;
char c;
sum[0]=0;
Max[0]=-1E9;
now=0;
for(i=0;i<Q;i++)
{
getchar();
c=getchar();
switch(c)
{
case 'I':
scanf("%d",&t);
a.push(t);
now++;
sum[now]=sum[now-1]+t;
Max[now]=max(Max[now-1],sum[now]);
break;
case 'D':
if(!a.empty())
{
a.pop();
now--;
}
break;
case 'L':
if(!a.empty())
{
b.push(a.top());a.pop();
now--;
}
break;
case 'R':
if(!b.empty())
{
a.push(b.top());b.pop();
now++;
sum[now]=sum[now-1]+a.top();
Max[now]=max(Max[now-1],sum[now]);
}
break;
case 'Q':
scanf("%d",&t);
printf("%d\n",Max[t]);
break;
}
}
}
}
最后更新：2017-04-03 16:49:00