poj1160Post Office(DP)
http://poj.org/problem?id=1160
算水过的吧 四重循环没优化 CZ说爆可过 就爆了
dp[i][j] = min(dp[i][j],dp[i-1][g]-s) 第i个点建在第j个村庄上 s 是这个点比上个点少的距离
1 #include <iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<algorithm> 5 #include<stdlib.h> 6 #include<cmath> 7 using namespace std; 8 #define N 1010 9 #define INF 0xfffffff 10 int h[N],dp[40][N]; 11 int main() 12 { 13 int i,j,k,n,m,g; 14 scanf("%d%d",&n,&m); 15 for(i = 1; i <= n; i++) 16 scanf("%d",&h[i]); 17 for(i = 1; i <= n ; i++) 18 { 19 int s = 0; 20 for(j = 1; j <= n ; j++) 21 s+=abs(h[j]-h[i]); 22 dp[1][i] = s; 23 } 24 for(i = 2 ; i <= m ; i++) 25 for(j = i ; j <= n ; j++) 26 { 27 dp[i][j] = INF; 28 for(g = i-1; g < j ; g++) 29 { 30 int s=0,ss=0; 31 for(k = g+1 ; k < j; k++) 32 { 33 s+=min(h[k]-h[g],h[j]-h[k]); 34 ss+=(h[k]-h[g]); 35 } 36 dp[i][j] = min(dp[i][j],dp[i-1][g]-ss-(h[j]-h[g])*(n-j+1)+s); 37 } 38 } 39 int minz=INF; 40 for(i = m; i <= n ; i++) 41 minz = min(minz,dp[m][i]); 42 printf("%d\n",minz); 43 return 0; 44 }