added multiplication by riesel prime

src/multiplication.c

@@ -255,7 +255,7 @@ int karatsuba_multi(int num1, int num2) {
     return ac * (int)pow(10, 2 * m2) + ad_bc * (int)pow(10, m2) + bd;
 }
 
-int multiply_by_riesel_prime(int num) {
+int multi_by_riesel_prime(int num) {
     return (num << 2) + (num << 3) - (num << 1) - num;
 }
 

src/multiplication.h

@@ -32,7 +32,7 @@ int bernoulli_multi(int num, int bernoulli);
 float power_multi(float base, int exponent);
 int bitwisee_multi(int num1, int num2);
 int karatsuba_multi(int num1, int num2);
-int multiply_by_riesel_prime(int num);
+int multi_by_riesel_prime(int num);