1 Print a given matrix in spiral form

Given a 2D array, print it in spiral form. See the following examples.

Input:

        1    2   3   4

        5    6   7   8

        9   10  11  12

        13  14  15  16

Output:

1 2 3 4 8 12 16 15 14 13 9 5 6 7 11 10

Input:

        1   2   3   4  5   6

        7   8   9  10  11  12

        13  14  15 16  17  18

Output:

1 2 3 4 5 6 12 18 17 16 15 14 13 7 8 9 10 11

Solution:

#include <stdio.h> #define R 3 #define C 6 void spiralPrint(int m, int n, int a[R][C]) {     int i, k = 0, l = 0;     /*  k - starting row index         m - ending row index         l - starting column index         n - ending column index         i - iterator     */     while (k < m && l < n)     {         /* Print the first row from the remaining rows */         for (i = l; i < n; ++i)         {             printf("%d ", a[k][i]);         }         k++;         /* Print the last column from the remaining columns */         for (i = k; i < m; ++i)         {             printf("%d ", a[i][n-1]);         }         n--;         /* Print the last row from the remaining rows */         if ( k < m)         {             for (i = n-1; i >= l; --i)             {                 printf("%d ", a[m-1][i]);             }             m--;         }         /* Print the first column from the remaining columns */         if (l < n)         {             for (i = m-1; i >= k; --i)             {                 printf("%d ", a[i][l]);             }             l++;            }            } } /* Driver program to test above functions */ int main() {     int a[R][C] = { {1,  2,  3,  4,  5,  6},         {7,  8,  9,  10, 11, 12},         {13, 14, 15, 16, 17, 18}     };     spiralPrint(R, C, a);     return 0; } /* OUTPUT:   1 2 3 4 5 6 12 18 17 16 15 14 13 7 8 9 10 11 */ Please Leave comment if you have doubts. Give ur solution thru comments.