SRM525 dropcoin editorial

getMinimum.java

public int getMinimum(String[] board, int K)
{
    int w = board.length;
    int h = board[0].length();
    final int INF = 1000000000; //A large number
    int res = INF;
    
    // For each subrectangle of the board:
    for (int x0 = 0; x0 < w; x0 ++) {
     for (int x1 = x0+1; x1 <= w; x1++) {
        for (int y0 = 0; y0 < h; y0 ++) {
         for (int y1 = y0+1; y1 <= h; y1++) {
             // Count the coins inside the subrectangle:
             int coins = 0;
             for (int i=x0; i<x1; i++) {
                 for (int j=y0; j<y1; j++) {
                     if (board[i].charAt(j)=='o') {
                         coins ++;
                     }
                 }
             }
             // If there are K coins, find the minimum number of moves to
             // end with that subrectangle. Remember the minimum overall.
             if (coins == K) {
                 int a = x0;     //number of left columns  to remove.
                 int b = w - x1; //number of right columns to remove
                 int c = y0;     //number of top rows to remove
                 int d = h - y1; //number of bottom rows to remove.
                 res = Math.min(res,  a+b+c+d + Math.min(a,b) + Math.min(c,d) );
             }
         }
        }
     }
    }
    return ( (res==INF) ? -1 : res);
}