#include<iostream.h>

char str[5010];
short answer[5010][5010];


int main()
{
	int length;
	cin>>length>>str;
	//for(short k=0;k<length;k++)
	//{
		answer[length][0]=0;
		answer[length-1][1]=0;
	//}
	
	for(short i=2;i<=length;i++)
	{
		for(short j=0;j+i<=length;j++)
		{ 
			if(str[j]!=str[i+j-1])
				answer[j][i]=(answer[j][i-1]<answer[j+1][i-1]?answer[j][i-1]+1:answer[j+1][i-1]+1);		
			else
				answer[j][i]=answer[j+1][i-2];		
	}
	
	cout<<answer[0][length]<<endl;
	return 0;
}

• Re:为什么还是超时!555555555555 (34) hot 2005-11-29 22:04:39