public int minPathSum(int[][] grid) {

int n = grid.length;

int m = grid[0].length;

int[][] dp = new int[n][m];

dp[0][0] = grid[0][0];

for (int i = 1; i < n; i++)

dp[i][0] = grid[i][0] + dp[i - 1][0];

for (int i = 1; i < m; i++)

dp[0][i] = grid[0][i] + dp[0][i - 1];

for (int i = 1; i < n; i++)

for (int j = 1; j < m; j++)

dp[i][j] = grid[i][j] + Math.min(dp[i - 1][j], dp[i][j - 1]);

return dp[n - 1][m - 1];

}

public static void main(String[] args) {

MinimumPathSum sln = new MinimumPathSum();

int[][] g1 = new int[][] {

{ 1, 3, 1 },

{ 1, 5, 1 },

{ 4, 2, 1 } };

System.out.println(sln.minPathSum(g1)); // 7

System.out.println(sln.minPathSum(new int[][] {{1}})); // 1

}