added sort check to guarantee correct sorting

1 files changed, 22 insertions, 9 deletions

diff --git a/main.c b/main.c
index 054d6e3..befea87 100644
--- a/main.c
+++ b/main.c
@@ -3,6 +3,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <pthread.h>
+#include <string.h>
 
 int sortMe[] = {9,8,7,6,5,4,3,2,1,0,22,2,39,88,56,4,42,2,5};
 #define NUM_THREADS sizeof(sortMe)/sizeof(sortMe[0])
@@ -13,8 +14,9 @@ int counter;
 
 void *sleepMe(int *p)
 	{
-	usleep((*p)*500);// *200 will do, but *500 is needed to reliably attain a correct order for numbers only 1 apart
-
+	/* a sleep amount of 190✕ makes it faster */
+	usleep((*p)*190);
+	
 	pthread_mutex_lock(&lock);
 	result[counter++] = *p;
 	pthread_mutex_unlock(&lock);
@@ -23,18 +25,29 @@ void *sleepMe(int *p)
 int main()
 {
 	pthread_t threads[NUM_THREADS];
-	int c = NUM_THREADS;//number of threads to create
+	int c, thread;
+	reshuffle: c = NUM_THREADS; //number of threads to create
+	counter = 0;
+	thread = 0;
 
-	int thread = 0;
-	while (c--){pthread_create(&threads[thread++], NULL, (void *)sleepMe, &sortMe[c]);}//create a thread for each number in the array
+	/* create a thread for each number in the array */
+	while (c--){pthread_create(&threads[thread++], NULL, (void *)sleepMe, &sortMe[c]);}
 
-	for (int i = 0; i < thread; ++i){pthread_join(threads[i], NULL);}//join all the threads, when all are joined, writing to the result array is done
+	/* join all the threads, when all are joined, writing to the result array is done */
+	for (int i = 0; i < thread; ++i){pthread_join(threads[i], NULL);}
 
+	/* check if the array is sorted and re-sort if not */
+	for (int i = 1; i < NUM_THREADS-1; ++i)
+		{
+		if (result[i-1] > result[i]){memcpy(sortMe, result, sizeof(sortMe)); goto reshuffle;}
+		}
 
+	/* print the sorted array */
 	for (int i = 0; i < NUM_THREADS-1; ++i)
 		{
-		printf("%d,",result[i]);
+		printf("%d,", result[i]);
 		}
-	printf("%d\n",result[NUM_THREADS-1]);
-        return 0;
+   	printf("%d\n",result[NUM_THREADS-1]);
+	
+	return 0;
 }