HDU 4283

来源：互联网发布：美工培训机构编辑：程序博客网时间：2024/06/03 18:22

两种方法，不过先用next_pernutation先找出全排列再判断该排列的是否能符合栈模拟的规则的方法TLE，虽然TLE但是也提供了一种思路，也贴上吧

#include <stdio.h>#include <iostream>#include <string.h>#include <algorithm>using namespace std;#define LEN 101int n[LEN];int ans[LEN][LEN][LEN];int _min, num;int next[LEN];int judge(int* next) {int flag = 1;int i, j, index;for(i = 0; i < num-2; i++) {for(j = i+1; j < num-1; j++) {for(index = j+1; index < num; index++) {if(next[j] < next[index] && next[index] < next[i]) {flag = 0;}}}}return flag;}int main() {int files;int cases;int i, j, tmp;scanf("%d", &files);for(i = 0; i < 101; i++) {next[i] = i;}for(cases = 1; cases <= files; cases++) {_min = 99999;memset(ans, 0, sizeof(ans));scanf("%d", &num);for(i = 0; i < num; i++) {scanf("%d", &n[i]);}while (next_permutation(next, next+num)) {if(1 == judge(next)) {tmp = 0;for(i = 0; i < num; i++) {tmp += next[i]*n[i];}/*if(_min > tmp) {_min = tmp;for(i = 0; i < num; i++) {cout<< " "<< next[i];}cout<< endl;}*/}}printf("Case #%d: %d\n", cases, _min);}return 0;}

正确的是用动归：

#include<cstdio>int dp[101][101][101],arr[101];int search(int s,int e,int k){    if(s==e) return arr[s]*k;    if(s>e) return 0;    if(dp[s][e][k]!=-1) return dp[s][e][k];    int min=search(s+1,e,k+1)+arr[s]*k;    for(int i=s+1;i<=e;i++) {         int l=search(s+1,i,k);         int r=search(i+1,e,(k+i+1-s));         int temp=arr[s]*(k+i-s);         int ts=l+r+temp;         if(ts<min) min=ts;    }    dp[s][e][k]=min;    return min;}int main(){    int t,n;    scanf("%d",&t);    for(int cas=1;cas<=t;cas++) {         scanf("%d",&n);         for(int i=0;i<n;i++){              for(int j=0;j<n;j++) {                   for(int k=0;k<n;k++) dp[i][j][k]=-1;              }         }         for(int i=0;i<n;i++) scanf("%d",&arr[i]);         search(0,n-1,0);         printf("Case #%d: %d\n",cas,dp[0][n-1][0]);    }    return 0;}