#include<cstdio>
#include<cstring>
char a[5010];
char res[5010][5010];
int getMin(int i , int j)
{
	int min=6000 ,m;
	if(res[i][j] != -1)
		return res[i][j];
	if(i >= j)          
		return 0;
	if(a[i] == a[j])
		min = getMin(i+1,j-1);
/*	m1=getMin(i+1,j)+1;
	if(m1 < min)
		min = m1;
	m2=getMin(i,j-1)+1;
	if(m2 < min)
		min = m2;*/
	else
	{
		min = getMin(i+1,j)+1;
		m = getMin(i,j-1)+1;
		if(m<min)
			min=m;
	}
	res[i][j]=min;
	return min;

}
int main()
{
	int min;
	int n;
	while(scanf("%d",&n)!=EOF)
	{
		memset(res,255,sizeof(res));
		scanf("%s",a);
		min=getMin(0,n-1);
		printf("%d\n",min);
	}
	return 0;
}

• 不需要scanf("%d",&n) != EOF，只有一组数据 (0) zentropy 2008-02-19 22:39:11