LeetCode 64. Minimum Path Sum

描述

解决

class Solution {
public:
int minPathSum(vector<vector<int>>& grid) {
int r = grid.size();
if (r == 0)
return 0;
int l = r ? grid[0].size() : 0;
vector<vector<int>> dp(r, vector<int>(l, 0));
for (int i = 0; i < l; ++i)
{
if (i != 0)
{
dp[0][i] = dp[0][i - 1] + grid[0][i];
}
else if (i == 0)
{
dp[0][i] = grid[0][i];
}
}
for (int i = 0; i < r; ++i)
{
if (i != 0)
{
dp[i][0] = dp[i - 1][0] + grid[i][0];
}
else if (i == 0)
{
dp[i][0] = grid[i][0];
}
}
for (int i = 1; i < r; ++i)
{
for (int j = 1; j < l; ++j)
{
dp[i][j] = min(dp[i - 1][j], dp[i][j - 1]) + grid[i][j];
}
}
return dp[r - 1][l - 1];
}
};