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  1. #include <stdio.h>
  2.  
  3. #define MAX 20
  4.  
  5. void printSpiralMatrix(int n) {
  6.     int matrix[MAX][MAX];
  7.     int left = 0, right = n - 1, top = 0, bottom = n - 1;
  8.     int value = 1;
  9.  
  10.     for (int i = 0; i < n; i++) {
  11.         for (int j = 0; j < n; j++) {
  12.             matrix[i][j] = 0;
  13.         }
  14.     }
  15.  
  16.     while (value <= n * n) {
  17.         for (int i = left; i <= right; i++) {
  18.             matrix[top][i] = value++;
  19.         }
  20.         top++;
  21.  
  22.         for (int i = top; i <= bottom; i++) {
  23.             matrix[i][right] = value++;
  24.         }
  25.         right--;
  26.  
  27.         if (top <= bottom) {
  28.             for (int i = right; i >= left; i--) {
  29.                 matrix[bottom][i] = value++;
  30.             }
  31.             bottom--;
  32.         }
  33.  
  34.         if (left <= right) {
  35.             for (int i = bottom; i >= top; i--) {
  36.                 matrix[i][left] = value++;
  37.             }
  38.             left++;
  39.         }
  40.     }
  41.  
  42.     for (int i = 0; i < n; i++) {
  43.         for (int j = 0; j < n; j++) {
  44.             printf("%d ", matrix[i][j]);
  45.         }
  46.         printf("\n");
  47.     }
  48. }
  49.  
  50. int main() {
  51.     int n;
  52.     scanf("%d", &n);
  53.  
  54.     if (n > 0 && n <= 20) {
  55.         printSpiralMatrix(n);
  56.     }
  57.  
  58.     return 0;
  59. }
  60.  
Success #stdin #stdout 0s 5284KB
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https://ideone.com/pTpwMc
language:
C (gcc 8.3)
created:
4 days ago
visibility:
public

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