ITSA Problem 4.c

ITSA Problem 4.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void walk_through(int row, int column);

int size, input[20][20];
char output[20][20];

int flag = 0;

int main()
{
    while(scanf("%d", &size) != EOF) {
        for(int i = 0; i < size; i++) {
            for(int j = 0; j < size; j++) {
                scanf("%d", &input[i][j]);
                output[i][j] = input[i][j] + '0';

                //printf("%c", output[i][j]);
            }
            //printf("\n");
        }
        output[1][1] = '#';
        walk_through(1, 1);
        flag = 0;
        for(int i = 0; i < size; i++) {
            for(int j = 0; j < size; j++) {
                if(j != size - 1)
                    printf("%c ", output[i][j]);
                else
                    printf("%c", output[i][j]);
            }
            printf("\n");
        }

        return 0;
    }
}

void walk_through(int row, int column)
{
    if(row == size - 2 && column == size - 2) {
        flag = 1;
        return;
    }

    if(row + 1 < size && input[row + 1][column] != 1 && output[row + 1][column] != '#' && flag == 0) { /*down*/
        output[row + 1][column] = '#';
        walk_through(row + 1, column);
    }
    if(row - 1 >= 0 && input[row - 1][column] != 1 && output[row - 1][column] != '#' && flag == 0) { /*up*/
        output[row - 1][column] = '#';
        walk_through(row - 1, column);
    }
    if(column - 1 >= 0 && input[row][column - 1] != 1 && output[row][column - 1] != '#' && flag == 0) { /*left*/
        output[row][column - 1] = '#';
        walk_through(row, column - 1);
    }
    if(column + 1 < size && input[row][column + 1] != 1 && output[row][column + 1] != '#' && flag == 0) { /*right*/
        output[row][column + 1] = '#';
        walk_through(row, column + 1);
    }

    if(flag == 0) {
        output[row][column] = '*';
        return;
    }

}