dp 数字三角形

冻龟之前

先看地龟

 //
 // Created by snnnow on 2020/7/23
 //
 //递归算法，除了慢其实还好
 #include<iostream>
 #include<stdio.h>
 #include<stdlib.h>
 #include<time.h>
 #include <queue>
 using namespace std;
 #define Max 101
 int m[Max][Max];
 int n;
 int dfs(int a,int b){
     if(a==n)
         return m[a][b];
     return max(dfs(a+,b),dfs(a+,b+))+m[a][b];
 }
 int main(){

     scanf("%d",&n);
     for (int i = ; i <= n; ++i) {
         for (int j = ; j <= i ; ++j) {
             scanf("%d",&m[i][j]);

         }

     }
     printf("%d",dfs(,));
 }

加个记忆化搜素

 //
 // Created by snnnow on 2020/7/23
 //
 //递归算法，除了慢其实还好
 #include<iostream>
 #include<stdio.h>
 #include<stdlib.h>
 #include<time.h>
 #include <queue>
 #include <time.h>
 using namespace std;
 #define Max 101
 int m[Max][Max];
 int rem[Max][Max];
 int n;
 int dfs(int a,int b){
     if(rem[a][b]!=-)
         return rem[a][b];
     if(a==n)
         rem[a][b]= m[a][b];
     else
         rem[a][b]=max(dfs(a+,b),dfs(a+,b+))+m[a][b];

     return rem[a][b];
 }
 int main(){

     scanf("%d",&n);
     for (int i = ; i <= n; ++i) {
         for (int j = ; j <= i ; ++j) {
             scanf("%d",&m[i][j]);
             rem[i][j]=-;

         }

     }
     printf("%d",dfs(,));
     cout<<endl;
     printf("Time used = %.2f\n", (double)clock() / CLOCKS_PER_SEC);

 }