算法问题实战策略 JUMPGAME 记忆化搜索

地址 https://algospot.com/judge/problem/read/JUMPGAME

每次我们可以选择 右或者下移动当前数字 x+num || y+num

但是遍历过于低效 会TLE

我们需要建立一个记录 记录当前的格子是否已经遍历过 如果已经遍历过直接取其记录的结果即可(当前格子是否已经遍历 遍历的结果是可以到达还是不能到达)

代码如下

#include <iostream>
#include <vector>

using namespace std;

/*
2
7
2 5 1 6 1 4 1
6 1 1 2 2 9 3
7 2 3 2 1 3 1
1 1 3 1 7 1 2
4 1 2 3 4 1 2
3 3 1 2 3 4 1
1 5 2 9 4 7 0
7
2 5 1 6 1 4 1
6 1 1 2 2 9 3
7 2 3 2 1 3 1
1 1 3 1 7 1 2
4 1 2 3 4 1 3
3 3 1 2 3 4 1
1 5 2 9 4 7 0
*/
vector<vector<int>> v(150,vector<int>(150));
vector<vector<int>> vis(150, vector<int>(150));
int n; int m;

int jump(int x,int y)
{
    if (x >= m || x<0 || y <0 || y >= m) return -1;
    if (vis[x][y] == 1)
        return 0;
    vis[x][y] = 1;
    if (x == m - 1 && y == m - 1) 
        return 1;
    int jumpcount = v[x][y];
    int ret1 = jump(x + jumpcount, y);
    int ret2 = jump(x,y+ jumpcount);
    
    if (ret1 == 1 || ret2 == 1)
        return 1;
    return -1;
}


void solve()
{
    int x = 0, y = 0;

    int ret = jump(0,0);
    if (ret == 1) {
        cout << "YES" << endl;
    }
    else {
        cout << "NO" << endl;
    }
}

int main()
{
    cin >> n;
    while (n--) {
        for (int i = 0; i < 150; i++)
            for (int j = 0; j < 150; j++)
                v[i][j] = 0;
        for (int i = 0; i < 150; i++)
            for (int j = 0; j < 150; j++)
                vis[i][j] = 0;


        cin >> m;
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < m; j++) {
                cin >> v[i][j];
            }
        }

        solve();
    }


    return 0;
}