4843094_wa.cpp

部分PKU上的源码

#include<iostream>
using namespace std;
int n;
char x[5010];
char y[5010];
int next[5010];
int main()
{
	cin>>n;
	int i;
	for(i=1;i<=n;i++){cin>>x[i];y[n+1-i]=x[i];}
	for(i=1;i<=n;i++)
	{
		if(x[i]==y[i]) next[i]=next[i-1]+1;
		else next[i]=next[i-1];
		//cout<<next[i]<<" ";
	}
	cout<<n-next[n]<<endl;
	return 0;
}