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#include <stdio.h>
#include <string.h> // memset()

int main(void)
{
    int size;
    printf("Enter size of magic square (odd 1-99): ");
    scanf("%d", &size);

    if (size < 1 || size % 2 == 0) {
        printf("Size must be an odd integer between 1 and 99.");
        return 0;
    }        

    int row = 0, col = size/2, sizesize = size*size, square[size][size];
    memset(square, 0, sizeof(square));  // init table to 0
    square[row][col] = 1;

    for (int i = 2; i < sizesize + 1; i++) {
        int uprow = row == 0 ? size - 1 : row - 1;
        int rtcol = col == size - 1 ? 0 : col + 1;

        if (square[uprow][rtcol])
            row = row == size - 1 ? 0 : row + 1;
        else {
            row = uprow;
            col = rtcol;
        }

        square[row][col] = i;
    }

    putchar('\n');   // print table
    for (row = 0; row < size; row++) {
        for (col = 0; col < size; col++)
            printf("%5d", square[row][col]);
        putchar('\n');
    }

    return 0;
}