diff --git a/README b/README
index e5798f1..ef280e3 100644
--- a/README
+++ b/README
@@ -6,3 +6,55 @@ Pour lancer :
 
 ./student_rank <Nombre etudiants> <Nombre notes par etudiants> <mode debug (0 ou 1)>
 
+## Reponse
+
+index % time self children called name
+<spontaneous>
+[1] 100.0 0.00 4.03 main [1]
+0.01 4.00 1/1 sort_students [2]
+0.01 0.00 1/1 generate_ranks [5]
+0.00 0.01 1/1 generate_grades [7]
+0.00 0.00 2/2 free_array [8]
+
+---
+
+                0.01    4.00       1/1           main [1]
+
+[2] 99.6 0.01 4.00 1 sort_students [2]
+0.81 3.19 1000000/1000000 find_rank_student [3]
+0.00 0.00 1000/1001000 bubblesort [4]
+
+---
+
+                0.81    3.19 1000000/1000000     sort_students [2]
+
+[3] 99.3 0.81 3.19 1000000 find_rank_student [3]
+3.19 0.00 1000000/1001000 bubblesort [4]
+
+---
+
+                0.00    0.00    1000/1001000     sort_students [2]
+                3.19    0.00 1000000/1001000     find_rank_student [3]
+
+## [4] 79.2 3.19 0.00 1001000 bubblesort [4]
+
+                0.01    0.00       1/1           main [1]
+
+## [5] 0.2 0.01 0.00 1 generate_ranks [5]
+
+                0.01    0.00    1000/1000        generate_grades [7]
+
+## [6] 0.1 0.01 0.00 1000 generate_array [6]
+
+                0.00    0.01       1/1           main [1]
+
+[7] 0.1 0.00 0.01 1 generate_grades [7]
+0.01 0.00 1000/1000 generate_array [6]
+
+---
+
+                0.00    0.00       2/2           main [1]
+
+## [8] 0.0 0.00 0.00 2 free_array [8]
+
+On peut voir que le programme perds son temps sur le tri (79.2% du temps d'execution est dédié à l'execution de la fonction de tri).
diff --git a/gmon.out b/gmon.out
new file mode 100644
index 0000000..e64fb38
Binary files /dev/null and b/gmon.out differ
diff --git a/student_rank b/student_rank
new file mode 100755
index 0000000..e7cb851
Binary files /dev/null and b/student_rank differ
diff --git a/student_rank.c b/student_rank.c
index af84003..b938b10 100644
--- a/student_rank.c
+++ b/student_rank.c
@@ -4,122 +4,101 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include "heapsort.h"
-#include "bubblesort.h"
 
-void generate_grades(int** students_array, int students_number, int grades_number)
-{
-    int i = 0;
-    for(i=0;i<students_number;i++)
-    {
-	students_array[i] = (int*) malloc(grades_number*sizeof(int));
-        generate_array(students_array[i],grades_number);
+void generate_grades(int **students_array, size_t students_number, size_t grades_number) {
+    for (size_t i = 0; i < students_number; i++) {
+        students_array[i] = malloc(grades_number * sizeof(int));
+        generate_array(students_array[i], grades_number);
     }
 }
 
-void generate_ranks(int** students_array, int students_number, int grades_number)
-{
-    int i = 0;
-    int j = 0;
-    for(i=0;i<students_number;i++)
-    {
-	students_array[i] = (int*) malloc(grades_number*sizeof(int));
-        for(j=0;j<grades_number;j++)
-	{
+void generate_ranks(int **students_array, size_t students_number, size_t grades_number) {
+    for (size_t i = 0; i < students_number; i++) {
+        students_array[i] = calloc(grades_number, sizeof(int));
+        for (size_t j = 0; j < grades_number; j++) {
             students_array[i][j] = -1;
-	}
+        }
     }
 }
 
-void free_array(int** students_array, int students_number)
-{
-    int i = 0;
-    for(i=0;i<students_number;i++)
-    {
+void free_array(int **students_array, size_t students_number) {
+    for (size_t i = 0; i < students_number; i++) {
         free(students_array[i]);
     }
 }
 
-void print_student_array(int** students_array, int students_number, int grades_number)
-{
-    int i = 0;
+void print_student_array(int **students_array, size_t students_number, size_t grades_number) {
     printf("----------------------\n");
-    for(i=0;i<students_number;i++)
-    {
-	printf("Student %d : ",i);
-        print_array(students_array[i],grades_number);
+    for (size_t i = 0; i < students_number; i++) {
+        printf("Student %zu : ", i);
+        print_array(students_array[i], grades_number);
     }
     printf("----------------------\n");
 }
 
-int find_rank_student(int student_grade, int* grades_array, int students_number)
-{
-    int position = -1;
-    int i = 0;
-    bubblesort(grades_array,students_number);
-    for(i = students_number-1; i >= 0; i--)
-    {
-        if(grades_array[i] == student_grade)
-	{
-            position = students_number-i;
-	    break;
-	}
+int find_rank_student(int student_grade, int *grades_array, size_t students_number) {
+    for (size_t i = 0; i < students_number; i++) {
+        if (grades_array[i] == student_grade) {
+            return i + 1;
+        }
     }
-    return position;
+    return -1;
 }
 
-void sort_students(int** students_rank, int** students_array, int students_number, int grades_number)
-{
-    int i = 0, j = 0;
-    for(i = 0; i < grades_number; i++)
-    {
-        int * grades = (int*) malloc(students_number*sizeof(int));
-	for(j = 0; j < students_number; j++)
-	{
-	    grades[j] = students_array[j][i];
-	}
-        bubblesort(grades,students_number);
-	for(j = 0; j < students_number; j++)
-	{
-            students_rank[j][i] = find_rank_student(students_array[j][i],grades,students_number);
-	}
-	free(grades);
+void sort_students(int **students_rank, int **students_array, size_t students_number, size_t grades_number) {
+    int *grades = malloc(students_number * sizeof(int));
+    int *sorted_grades = malloc(students_number * sizeof(int));
+    int *sums = calloc(students_number, sizeof(int));
+
+    for (size_t i = 0; i < grades_number; i++) {
+        for (size_t j = 0; j < students_number; j++) {
+            sums[j] += students_array[j][i];
+            grades[j] = sums[j] / (i + 1);
+            sorted_grades[j] = grades[j];
+        }
+
+        heapsort(sorted_grades, students_number);
+        for (size_t j = 0, k = students_number - 1; j < k; j++, k--) {
+            int temp = sorted_grades[j];
+            sorted_grades[j] = sorted_grades[k];
+            sorted_grades[k] = temp;
+        }
+
+        for (size_t j = 0; j < students_number; j++) {
+            students_rank[j][i] = find_rank_student(grades[j], sorted_grades, students_number);
+        }
     }
+
+    free(grades);
+    free(sorted_grades);
+    free(sums);
 }
 
-int main(int argc, char** argv)
-{
-    int** student_grades = NULL;
-    int** student_ranks = NULL;
-    int students_length = 0;
-    int grades_length = 0;
-    int debug_mode = 0;
-    
-    if(argc != 4)
-    {
-        printf("Usage : %s <number of student> <number of grade per student> <debug mode : 0|1>\n",argv[0]);
+int main(int argc, char **argv) {
+    if (argc != 4) {
+        printf("Usage : %s <number of student> <number of grade per student> <debug mode : 0|1>\n", argv[0]);
         return -1;
     }
-    students_length = atoi(argv[1]);
-    grades_length = atoi(argv[2]);
-    debug_mode = atoi(argv[3]);
 
-    student_grades = (int**) malloc(students_length*sizeof(int*));
-    student_ranks = (int**) malloc(students_length*sizeof(int*));
-    generate_grades(student_grades,students_length,grades_length);
-    generate_ranks(student_ranks,students_length,grades_length);
-    
-    sort_students(student_ranks,student_grades,students_length,grades_length);
-    
-    if(debug_mode)
-    {
-        print_student_array(student_grades,students_length,grades_length);
-        print_student_array(student_ranks,students_length,grades_length);
+    size_t students_length = atoi(argv[1]);
+    size_t grades_length = atoi(argv[2]);
+    int debug_mode = atoi(argv[3]);
+
+    int **student_grades = malloc(students_length * sizeof(int *));
+    int **student_ranks = malloc(students_length * sizeof(int *));
+    generate_grades(student_grades, students_length, grades_length);
+    generate_ranks(student_ranks, students_length, grades_length);
+
+    sort_students(student_ranks, student_grades, students_length, grades_length);
+
+    if (debug_mode) {
+        print_student_array(student_grades, students_length, grades_length);
+        print_student_array(student_ranks, students_length, grades_length);
     }
 
-    free_array(student_grades,students_length);
-    free_array(student_ranks,students_length);
+    free_array(student_grades, students_length);
+    free_array(student_ranks, students_length);
     free(student_grades);
     free(student_ranks);
     return 0;
 }
-