leetcode 064 —— Minimum Path Sum

Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.

Note: You can only move either down or right at any point in time.

思路：动态规划

class Solution {
public:
	int minPathSum(vector<vector<int>>& grid) {
		int m = grid.size();
		int n = grid[0].size();
		for (int i = 1; i < m; i++)
			grid[i][0] += grid[i - 1][0];
		for (int i = 1; i < n; i++)
			grid[0][i] += grid[0][i - 1];
		for (int i = 1; i < m; i++)
		for (int j = 1; j < n; j++)
			grid[i][j] += min(grid[i - 1][j], grid[i][j - 1]);
		return grid[m - 1][n - 1];	
	}
};