#include <iostream>
using namespace std;
int pisa[100001][11];
int sum[100001][11];
int T;
int maxSum(int a, int b, int c)
{
    int max(0);
    if (a>max)
        max=a;
    if (b>max)
        max=b;
    if (c>max)
        max=c;
    return max;
}
int mypisa(int r, int j)
{
    if (r==T)
        return sum[r][j];
    if (j==0)
    {
        if (sum[r+1][j]==-1)
            sum[r+1][j]=mypisa(r+1,j);
        if (sum[r+1][j+1]==-1)
            sum[r+1][j+1]=mypisa(r+1,j+1);
        if (sum[r+1][j] > sum[r+1][j+1])
            return sum[r+1][j] + pisa[r][j];
        return sum[r+1][j+1] + pisa[r][j];
    }
    else if (j==10)
    {
        if (sum[r+1][j]==-1)
            sum[r+1][j]=mypisa(r+1,j);
        if (sum[r+1][j-1]==-1)
            sum[r+1][j-1]=mypisa(r+1,j-1);
        if (sum[r+1][j] > sum[r+1][j-1])
            return sum[r+1][j] + pisa[r][j];
        return sum[r+1][j-1] + pisa[r][j];
    }
    else
    {
        if (sum[r+1][j-1]==-1)
            sum[r+1][j-1]=mypisa(r+1,j-1);
        if (sum[r+1][j]==-1)
            sum[r+1][j]=mypisa(r+1,j);
        if (sum[r+1][j+1]==-1)
            sum[r+1][j+1]=mypisa(r+1,j+1);
        return
            maxSum(sum[r+1][j-1],sum[r+1][j],sum[r+1][j+1])
            + pisa[r][j];
    }
}
int main()
{
    int x, t, n;
    while (cin>>n && n!=0)
    {
        memset(sum,-1,sizeof(sum));
        memset(pisa,0,sizeof(pisa));
        T=0;
        for (int i=0; i<n; i++)
        {
            cin >>x>>t;
            pisa[t][x]++;
            if (t>T)
                T=t;
        }
        for (i=0; i<=10; i++)
            sum[T][i]=pisa[T][i];
        cout <<mypisa(0,5)<<endl;
    }
    return 0;
}
这是杭电acm免费馅饼问题，
输入
1
1 10000
结果正确
输入
1
1 20000
就会出错。提交结果是栈溢出，请高手帮忙！谢谢！