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.
public class Solution {
public int minPathSum(int[][] grid) {
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<col;i++){
dp[0][i]=grid[0][i]+dp[0][i-1];
}
for(int j=1;j<row;j++){
dp[j][0]=grid[j][0]+dp[j-1][0];
}
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];
}
}
dp[i][j]的值代表最左上角的位置到当前位置最短路径。注意边界问题。