Driver program to test above function
int main ( ) { int test_no = 64 ; if ( isPowerOfFour ( test_no ) ) printf ( " % d ▁ is ▁ a ▁ power ▁ of ▁ 4" , test_no ) ; else printf ( " % d ▁ is ▁ not ▁ a ▁ power ▁ of ▁ 4" , test_no ) ; getchar ( ) ; }