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]}

View Code

 1 #include <stdio.h>

 2 #include<string.h>

 3 int dp[100001][12];

 4 int max1(int x, int y, int z)

 5 {

 6     int m = x;

 7     if(m<y)

 8     m = y;

 9     if(m<z)

10     m = z;

11     return m;

12 }

13 int main()

14 {

15     int n,i, j,b,t;

16     while(scanf("%d", &n)&&n)

17     {

18         int max = 0;

19         memset(dp,0,sizeof(dp));

20         for(i = 1 ; i <= n ; i++)

21         {

22             scanf("%d%d",&b,&t);

23             dp[t][b]++;

24             if(t>max)

25             max = t;

26         }

27         dp[0][5] = 0;

28         for(i = max-1 ; i >= 0 ; i--)

29         for(j = 0 ; j <= 10 ; j++)

30         {

31             if(j==0)

32             {

33                 if(dp[i+1][j]>dp[i+1][j+1])

34                 dp[i][j] += dp[i+1][j];

35                 else

36                 dp[i][j] += dp[i+1][j+1];

37             }

38             else

39             if(j == 10)

40             {

41                 if(dp[i+1][j]>dp[i+1][j-1])

42                 dp[i][j] += dp[i+1][j];

43                 else

44                 dp[i][j] += dp[i+1][j-1];

45             }

46             else

47             {

48                 dp[i][j] += max1(dp[i+1][j],dp[i+1][j+1],dp[i+1][j-1]);

49             }

50         }

51         printf("%d\n",dp[0][5]);

52     }

53     return 0;

54 }