原题目
Describe:贪心,左边和右边中选字典序小的
code:
#include<bits/stdc++.h>
using namespace std;
int n,step,head,tail;
char p[50005];
int main()
{freopen("bcl.in","r",stdin);freopen("bcl.out","w",stdout);cin>>n;head=1,tail=n;for(int i=1;i<=n;i++)cin>>p[i];while(head<tail){if(p[head]<p[tail])putchar(p[head]),head++;else if(p[head]>p[tail])putchar(p[tail]),tail--;else{int i=head,j=tail;while(i<j&&p[i]==p[j])i++,j--;if(p[i]<p[j])putchar(p[head]),head++;else putchar(p[tail]),tail--;}step++,step%=80;if(!step)puts("");}putchar(p[head]);return 0;
}