Dungeon Game Solutions in C++

// Source : https://oj.leetcode.com/problems/dungeon-game/
// Author : Hao Chen
// Date   : 2015-01-16



class Solution {
    public:
        int calculateMinimumHP(vector<vector<int> > &dungeon) {
            int row = dungeon.size();
            int col = row>0 ? dungeon[0].size() : 0;
            if (row<=0 || col <=0) return 0;

            //dp[r][c] = min( max( dp[r+1][c] - dungeon[r][c], 1), max( dp[r][c+1] - dungeon[r][c], 1) );
            int dp[row][col];
            memset(dp, 0, sizeof(dp));

            for(int r=row-1; r>=0; r--){
                for (int c=col-1; c>=0; c--){

                    /*if (r == row - 1 && c == col - 1 ){
                      dp[r][c] = max(1 - dungeon[r][c], 1);
                      }else if ( r == row - 1 ) {
                      dp[r][c] = max(dp[r][c+1] - dungeon[r][c], 1);
                      }else if ( c == col - 1 ) {
                      dp[r][c] = max(dp[r+1][c] - dungeon[r][c], 1);
                      }else{
                      dp[r][c] = min( max( dp[r+1][c] - dungeon[r][c], 1), max( dp[r][c+1] - dungeon[r][c], 1) );
                      }*/

                    if (r == row - 1 && c == col - 1 ){
                        dp[r][c] = max(1 - dungeon[r][c], 1);
                    }else{ 
                        int h1 = ( c == col-1  ) ? INT_MAX : max(dp[r][c+1] - dungeon[r][c], 1);
                        int h2 =  ( r == row-1 ) ? INT_MAX : max(dp[r+1][c] - dungeon[r][c], 1);

                        dp[r][c] = min( h1, h2 );
                    }

                }
            }

            return dp[0][0];


        }
};