Minesweeper Numbers

talk open source
1

This is in JAVA, by the way…

This problem actually sounds much harder than it is. They gave you the rows and columns of a minesweeper game, and then list the mines. Your job, is to output the table, and show the number of mines touching each place (just like in Microsoft’s version). I made the table have a 1 number border on all sides to avoid out of bounds exceptions (each point inefficiently checks all neighboring points, as that was the quickest approach, and these contests are all about speed).

[size=5]USAGE[/size]

The 7 represents the rows, the 5 is the columns, and the 7 represents the number of following mines. Each mine is x, y, starting at top left.

7 5 7
1 4
5 2
5 3
2 5
3 3
4 4
4 2

Here’s what this will output

001*2
0123*
12*32
2*5*1
2**21
12210
00000

[size=5]SOURCE[/size]

import java.io.*;
import java.util.*;

public class pr91 {
	public static void main (String args[]) throws IOException {
		Scanner scanner = new Scanner (new FileReader("pr91.txt"));
		int rows = scanner.nextInt();
		int columns = scanner.nextInt();
		int mines = scanner.nextInt();
		
		int [][] table = new int [rows+2][columns+2]; // leave a border
		
		for (int i=0; i<mines; i++) {
			table[scanner.nextInt()][scanner.nextInt()] = -1;
		}
		
		for (int r=1; r<table.length-1; r++) {
			for (int c=1; c<table[r].length-1; c++) {
				if (table[r][c]>-1) {
					int sum = 0;
					if (table[r-1][c-1]==-1) sum++;
					if (table[r][c-1]==-1) sum++;
					if (table[r+1][c-1]==-1) sum++;
					if (table[r-1][c]==-1) sum++;
					if (table[r+1][c]==-1) sum++;
					if (table[r-1][c+1]==-1) sum++;
					if (table[r][c+1]==-1) sum++;
					if (table[r+1][c+1]==-1) sum++;
					
					table[r][c]=sum;
				}
			}
		}
		
		// Print
		for (int i=1; i<table.length-1; i++) {
			for (int j=1; j<table*.length-1; j++) {
				if (table*[j]==-1)
					System.out.print("*");
				else
					System.out.print(table*[j]);
			}
			
			System.out.println();
		}
	}
}

Keep in mind these contests are all about speed.

This uses Java 1.5.

Hope you like it. :smiley: