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  1. #include<stdio.h>
  2. #include<stdlib.h>
  3. #include<string.h>
  4.  
  5. void mergesort_(int a[], int b[], int l, int r);
  6. void mergesort(int a[], int n);
  7.  
  8. void mergesort_(int a[], int b[], int l, int r) {
  9. 	int c;
  10. 	int i;
  11. 	int j;
  12. 	int k;
  13. 	int n;
  14.  
  15. 	if (l >= r) {
  16. 		return;
  17. 	}
  18.  
  19. 	c = ((r - l) >> 1) + l;
  20. 	mergesort_(a, b, l, c);
  21. 	mergesort_(a, b, c + 1, r);
  22.  
  23. 	j = 0;
  24. 	for (i = l; i <= c; i++) {
  25. 		b[j] = a[i];
  26. 		j++;
  27. 	}
  28.  
  29. 	i = 0;
  30. 	k = c + 1;
  31. 	n = l;
  32.  
  33. 	while (k <= r) {
  34. 		if (j <= i) {
  35. 			return;
  36. 		}
  37.  
  38. 		if (b[i] <= a[k]) {
  39. 			a[n] = b[i];
  40. 			n++;
  41. 			i++;
  42. 		} else {
  43. 			a[n] = a[k];
  44. 			n++;
  45. 			k++;
  46. 		}
  47. 	}
  48.  
  49. 	while (i < j) {
  50. 		a[n] = b[i];
  51. 		n++;
  52. 		i++;
  53. 	}
  54. }
  55.  
  56. void mergesort(int a[], int n) {
  57. 	int *b = calloc(n >> 1, sizeof(int));
  58. 	mergesort_(a, b, 0, n - 1);
  59. 	free(b);
  60. }
  61.  
  62. int main(void) {
  63. 	FILE *fin;
  64. 	char buf[256];
  65. 	char *token;
  66. 	int nums[10];
  67. 	int i;
  68.  
  69. 	fin = fopen("numbers.dat", "r");
  70. 	fgets(buf, 256, fin);
  71. 	fclose(fin);
  72.  
  73. 	token = strtok(buf, " ");
  74. 	for (i = 0; i < 10; i++) {
  75. 		nums[i] = atoi(token);
  76. 		token = strtok(NULL, " ");
  77. 	}
  78.  
  79. 	mergesort(nums, 10);
  80.  
  81. 	for (i = 0; i < 10; i++) {
  82. 		printf("%d ", nums[i]);
  83. 	}
  84.  
  85. 	return 0;
  86. }
Runtime error #stdin #stdout 0.02s 1848KB
comments (?)
stdin 
Standard input is empty
stdout 
Standard output is empty
https://ideone.com/oeUHp
language:
C (gcc 8.3)
created:
11 years ago
visibility:
public

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