hdu 1176 馅饼

略微简单的动态规划

只是简单贴代码就好了。

#include <stdio.h>
#include <string.h>

int dp[100007][11];
int ans[100007][11];
int n,N;

inline int Max(int x,int c){
    return x>c?x:c;
}
int v[16];
void DP()
{
    int i,j;
    memset(v,0,sizeof(v));
    memset(ans,0,sizeof(ans));
    v[5]=v[4]=v[6]=1;
    int len = 2;
    for(i=1;i<=N+1;i++)
    {
        for(j=0;j<=10;j++)
        {
            if(v[j]){
                ans[i][j] = Max(dp[i][j]+ans[i-1][j],ans[i][j]);    
            }
            if(j-1>=0 &&v[j-1]){
                ans[i][j-1] = Max(dp[i][j-1]+ans[i-1][j],ans[i][j-1]);
            }
            if(j+1<=10&&v[j+1]){
                ans[i][j+1] = Max(dp[i][j+1]+ans[i-1][j],ans[i][j+1]);
            }
        }
        if(len<=5){
            v[5-len]=1,v[5+len]=1;
        }
        len++;
    }
    
    int _max = -1100000000;
    for(int x=0;x<=10;x++) 
        if(_max < ans[N+1][x]) _max = ans[N+1][x];
    printf("%d
",_max);
}

void show()
{
    for(int i=1;i<=N+1;i++){
        for(int x=0;x<=10;x++){
            printf("%d ",ans[i][x]);
        }
        puts("");
    }
}

int main()
{
    int i;
    while(scanf("%d",&n),n){
        memset(dp,0,sizeof(dp));
        for(i=1;i<=n;i++){
            int ti,pot;
            scanf("%d%d",&pot,&ti);
            dp[ti][pot]++;
            if(ti > N) N = ti;
        }
        DP();
        //show();
    }
    return 0;
}