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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; } Followed by:
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