#include <cstdio>
 
void print_bit_repr(int x) {
    for (int i = 1<<8; i > 0; i>>=1)
        printf("%c", (x & i) ? '1' : '0');
    printf("\n");
}
 
void set(int & x, int pos) { x |= (1 << pos); }
void unset(int & x, int pos) { x &= ~(1 << pos); }
bool is_set(int & x, int pos) { return x & (1 << pos); }
 
void unset_lowest_bit(int & x) { x &= (x-1); }
 
int main() {
    int a = 0;
 
    set(a, 1); print_bit_repr(a); 
    set(a, 2); print_bit_repr(a);
    for (int i = 0; i < 8; ++i)
        printf("%d is set : %s\n", i, is_set(a, i) ? "YES" : "NO");
    unset(a, 1); print_bit_repr(a); 
    unset(a, 2); print_bit_repr(a);
 
    set(a, 3); print_bit_repr(a); 
    set(a, 5); print_bit_repr(a);
    unset_lowest_bit(a); print_bit_repr(a); 
    unset_lowest_bit(a); print_bit_repr(a); 
 
    return 0;
}
 

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