hdu1176

看了看题 没什么想法 参考着解题报告写的

状态方程 dp[i][j] = max{dp[i+1][j],dp[i+1][j+1],dp[i+1][j-1]}

#include <stdio.h>
#include<string.h>
int dp[100001][12];
int max1(int x, int y, int z)
{
    int m = x;
    if(m<y)
    m = y;
    if(m<z)
    m = z;
    return m;
}
int main()
{
    int n,i, j,b,t;
    while(scanf("%d", &n)&&n)
    {
        int max = 0;
        memset(dp,0,sizeof(dp));
        for(i = 1 ; i <= n ; i++)
        {
            scanf("%d%d",&b,&t);
            dp[t][b]++;
            if(t>max)
            max = t;
        }
        dp[0][5] = 0;
        for(i = max-1 ; i >= 0 ; i--)
        for(j = 0 ; j <= 10 ; j++)
        {
            if(j==0)
            {
                if(dp[i+1][j]>dp[i+1][j+1])
                dp[i][j] += dp[i+1][j];
                else
                dp[i][j] += dp[i+1][j+1];
            }
            else
            if(j == 10)
            {
                if(dp[i+1][j]>dp[i+1][j-1])
                dp[i][j] += dp[i+1][j];
                else
                dp[i][j] += dp[i+1][j-1];
            }
            else
            {
                dp[i][j] += max1(dp[i+1][j],dp[i+1][j+1],dp[i+1][j-1]);
            }
        }
        printf("%d\n",dp[0][5]);
    }
    return 0;
}