addition for all unsigned integer (modulo UNIT_MAX)

src/addition.c

@@ -12,7 +12,7 @@ unsigned int addition(num number1, num number2) {
     num sum[1] = {0};
     num nextcarry[1] = {0};
 
-    for (int i = 0; i < 2; i++)
+    for (int i = 0; i < 8 * sizeof(num); i++)
     {
         full_adder(sum, nextcarry, number1, number2, nextcarry[0]);
         result ^= (sum[0] << i);