dp问题,确定状态转移方程
class Solution {
public:
int getMaxValue(vector<vector<int>>& grid) {
int n = grid.size(), m = grid[0].size();
vector<vector<int>> f(n+1, vector<int>(m+1, 0));
f[0][0] = 0;
for (int i = 1; i <= n; i ++) {
for (int j = 1; j <= m; j ++) {
f[i][j] = max(f[i-1][j], f[i][j-1]) + grid[i-1][j-1];
}
}
return f[n][m];
}
};