diff --git a/TP5/a.out b/TP5/a.out
index 3e71355..f4c157d 100755
Binary files a/TP5/a.out and b/TP5/a.out differ
diff --git a/TP5/carre.c b/TP5/carre.c
new file mode 100644
index 0000000..0c3e37a
--- /dev/null
+++ b/TP5/carre.c
@@ -0,0 +1,51 @@
+#include <stdio.h>
+
+#define N 3
+
+int main () {
+
+  // int A[N][N] = {1,2,3,4,5,6,7,8,9};  // Initialisation pas magique
+
+  int A[N][N] = {4,2,3,2,3,4,3,4,2};  // Initialisation pas magique
+
+ int i , j;
+
+ // diagonale
+
+ int sommed1 = 0, sommed2 = 0;
+ 
+ for(i=0;i<N;i=i+1)
+   {
+     sommed1 = sommed1 + A[i][i];
+     sommed2 = sommed2 + A[i][N-1-i];
+   }
+
+ if ( sommed1 != sommed2 )
+   {
+     printf("stop, pas magique\n");
+     return 1;
+   }
+
+ // hors diagonale
+int sommeV , sommeH ;
+for(i=0;i<N;i=i+1)
+  {
+    sommeH = 0 ;
+    sommeV = 0 ;
+    for (j=0;j<N;j++)
+      {
+        sommeH = sommeH + A[i][j] ;
+        sommeV = sommeV + A[j][i] ;
+           }
+     if ( sommeH != sommed1 || sommeV != sommed1 )
+   {
+     printf("stop, pas magique\n");
+     return 1;
+   }
+     
+  }
+
+ printf("carre magique = %d \n",sommed1);
+    return 1;
+
+  }
diff --git a/TP5/fileread.c b/TP5/fileread.c
index 41165c2..b40f8e7 100644
--- a/TP5/fileread.c
+++ b/TP5/fileread.c
@@ -5,12 +5,19 @@ int main () {
 float a = 1.;
 int b = 1 ;
   
-FILE *point = fopen("data.dat","r");
+ FILE *point = fopen("data.dat","r"); // ouverture file "r" lecture
 
- fscanf(point,"%f %d \n",&a,&b);
+ // test necessaire pour ouverture en lecture
+ if(point==NULL) {
+    puts("Echec de l'ouverture. Fin du programme.");
+    return 0;
+ }
 
- printf("%f %d \n",a,b);
+ 
+ fscanf(point,"%f %d \n",&a,&b); // lecture file
 
- fclose(point);
+ printf("%f %d \n",a,b);  // print
+
+ fclose(point);  // fermeture file
 
    }
diff --git a/TP5/filewrite.c b/TP5/filewrite.c
index 9e55c00..bdcb7c5 100644
--- a/TP5/filewrite.c
+++ b/TP5/filewrite.c
@@ -5,10 +5,10 @@ int main () {
 float a = 1.;
 int b = 1 ;
   
-FILE *point = fopen("data.dat","w");
+ FILE *point = fopen("data.dat","w"); // ouverture file "w" ecriture
 
- fprintf(point,"%f %d \n",a,b);
+ fprintf(point,"%f %d \n",a,b); // ecriure file
 
- fclose(point);
+ fclose(point); // fermeture
 
    }