【leetcode】【64】Minimum Path Sum

一、问题描述

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.

二、问题分析

还是dynamic programing。与【leetcode】【62】Unique Paths类似。

三、Java AC代码

public int minPathSum(int[][] grid) {if (grid==null || grid.length==0) {return 0;}int row = grid.length;int col = grid[0].length;int[][] dp = new int[row][col];dp[0][0] = grid[0][0];for (int i = 1; i < row; i++) {dp[i][0] = dp[i-1][0]+grid[i][0];}for (int i = 1; i < col; i++) {dp[0][i] = dp[0][i-1]+grid[0][i];}for (int i = 1; i < row; i++) {for (int j = 1; j < col; j++) {dp[i][j] = Math.min(dp[i-1][j], dp[i][j-1])+grid[i][j];}}return dp[row-1][col-1];}