http://poj.org/problem?id=2385
dp[i][j], i为第几分钟,j为走了几次。则dp[i,j]=max(dp[i-1,j-1], dp[i-1][j])+(data[i]==(j%2+1)?1:0)。对data[i]==(j%2+1)?1:0,若j为奇数,则其必在2号树下,所以+1,反之+0。
code:
#include <cstdio>
using namespace std;
int dp[1005][35];
int app[1001];
int max(int a,int b){
if(a>b)
return a;
return b;
}
int main(){
int i, j,t,w;
while(scanf("%d%d",&t,&w)!=EOF){
dp[0][0]=0;
for (i=1;i<=t;i++){
scanf("%d",&app[i]);
dp[i][0]=dp[i-1][0]+(app[i]==1?1:0);
}
for (j=1;j<=w;j++)
for (i=1;i<=t;i++)
dp[i][j]=max(dp[i-1][j-1],dp[i-1][j])+(app[i]==(j%2+1)?1:0);
printf("%d\n",dp[t][w]);
}
return 0;}
using namespace std;
int dp[1005][35];
int app[1001];
int max(int a,int b){
if(a>b)
return a;
return b;
}
int main(){
int i, j,t,w;
while(scanf("%d%d",&t,&w)!=EOF){
dp[0][0]=0;
for (i=1;i<=t;i++){
scanf("%d",&app[i]);
dp[i][0]=dp[i-1][0]+(app[i]==1?1:0);
}
for (j=1;j<=w;j++)
for (i=1;i<=t;i++)
dp[i][j]=max(dp[i-1][j-1],dp[i-1][j])+(app[i]==(j%2+1)?1:0);
printf("%d\n",dp[t][w]);
}
return 0;}