From: Jerome Benoit <jerome.benoit@sap.com>
Date: Sun, 5 Mar 2017 09:13:43 +0000 (+0100)
Subject: TP 2 exo3: randomly choose the pivot in quick sort
X-Git-Url: https://git.piment-noir.org/?p=Algorithmic_C.git;a=commitdiff_plain;h=569df90ab9f7e584fe5b8812320f8461c999647f

TP 2 exo3: randomly choose the pivot in quick sort

Signed-off-by: Jerome Benoit <jerome.benoit@sap.com>
---

diff --git a/TP2/exo3/exo3.c b/TP2/exo3/exo3.c
index f070f1f..29ebcb0 100644
--- a/TP2/exo3/exo3.c
+++ b/TP2/exo3/exo3.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 
 void permuter(int T[], int i1, int i2) {
     int tmp = T[i1];
@@ -14,7 +15,8 @@ void AfficheTab(int T[], int n) {
 
 void TriRapide(int T[], int n) {
     // The optimal pivot choice is the median value in the tab
-    int pivot = T[0];
+    int index_pivot = arc4random_uniform(n);
+    int pivot = T[index_pivot];
     int TP[n];
     int TG[n];
     int np = 0;