题目：

题解：

class Solution {public int calculateMinimumHP(int[][] dungeon) {int n = dungeon.length, m = dungeon[0].length;int[][] dp = new int[n + 1][m + 1];for (int i = 0; i <= n; ++i) {Arrays.fill(dp[i], Integer.MAX_VALUE);}dp[n][m - 1] = dp[n - 1][m] = 1;for (int i = n - 1; i >= 0; --i) {for (int j = m - 1; j >= 0; --j) {int minn = Math.min(dp[i + 1][j], dp[i][j + 1]);dp[i][j] = Math.max(minn - dungeon[i][j], 1);}}return dp[0][0];}
}