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好不容易ac了,贴个代码#include<iostream>
using namespace std;
/**
思路:dp[p][v]表示的是0~v这v+1个村庄内,建立p个邮局时最小距离和;那么
动态规划方程是 dp[p][v] = min( dp[p-1][k] + sum(k+1,v) ),k=(v-1)~0;
sum(i,j)表示第i到第j个村庄共享1个邮局的最小距离和。
最后输出dp[P][v-1]。
**/
namespace p1160{
int V,P;
const int NV=301,NP=31;
int dp[NP][NV]; // 由于算第i层时只和i-1层相关,可用轮转数组替代
int pos[NV]; //村庄坐标
int calSum(int i,int j); //计算第i到第j个村庄共享1个邮局的最小距离和
int minn(int i,int j){return i<j?i:j;}
};
using namespace p1160;
int main(void){
memset(dp,127,sizeof(dp)); //initial MAX
cin>>V>>P;
for(int i=0;i<V;i++){ //初始化只有一个邮局的情况
cin>>pos[i];
dp[1][i] = calSum(0,i);
}
for(int i=2;i<=P;i++){
for(int j=1;j<V;j++){
for(int k=j-1;k>=0;k--){
if(i-1>=k+1){ //more post office than village
dp[i][j] = minn(dp[i][j],calSum(k+1,j));
break;
}
else
dp[i][j] = minn(dp[i][j],dp[i-1][k]+calSum(k+1,j));
}
}
}
cout<<dp[P][V-1];
//system("pause");
return 0;
}
int p1160::calSum(int i,int j){
int ans = 0;
int pi=i,pj=j;
while(i<j){ // 每次考虑最外层的2个村庄,邮局一定要建立在它们中间,最短距离为 pos[j]-pos[i]
ans+=pos[j]-pos[i];
i++; j--;
}
return ans;
}
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