#include <stdio.h> #include <math.h> #define CHAR_BIT 8 #define INT_BIT CHAR_BIT*sizeof(unsigned int) void sb(unsigned int* a, unsigned char pos){ *a |= 1 << (INT_BIT-pos-1); } int getPosition(unsigned int a){ float logg = log2(a); return (INT_BIT - (int)floor(logg)) - 1; } int main(void) { unsigned int a = 0; sb(&a, 1); sb(&a, 2); sb(&a, 3); sb(&a, 5); sb(&a, 6); printf("Poisiton of first 1 is: %d\n", getPosition(a)); printf("Poisiton of first 0 is: %d\n", getPosition(~a)); return 0; }