added header file

7_Matrix_1x1/7_Matrix_1x1.c

@@ -1,12 +1,9 @@
-#include <stdio.h>
+#include "7_Matrix_1x1.h"
 
 int main() {
-    // setting the end of the array
-    int upTo = 20;
-
     // printing the values as matrix
-    for (int i = 1; i <= upTo; i++) {       // y axis
+    for (int i = 1; i <= UPTO; i++) {       // y axis
-        for (int j = 1; j <= upTo; j++) {   // x axis
+        for (int j = 1; j <= UPTO; j++) {   // x axis
             printf("%5i", (i*j));           // printing each value, i*j = the value
         }
         printf("\n");                       // end of line on x axis

7_Matrix_1x1/7_Matrix_1x1.h

@@ -0,0 +1,3 @@
+#include <stdio.h>
+
+#define UPTO 20         // maximum value