public int minPathSum(int[][] grid) {
		int n = grid.length;
		int m = grid[0].length;
		int[][] dp = new int[n][m];
		// initialization
		dp[0][0] = grid[0][0];
		for (int i = 1; i < n; i++) {
			dp[i][0] = dp[i - 1][0] + grid[i][0];
		}
		for (int j = 1; j < m; j++) {
			dp[0][j] = dp[0][j - 1] + grid[0][j];
		}
		for (int i = 1; i < n; i++)
			for (int j = 1; j < m; j++) {
				dp[i][j] = Math.min(grid[i][j] + dp[i - 1][j], grid[i][j]
						+ dp[i][j - 1]);
			}
		return dp[n - 1][m - 1];
	}