3. Check if K-th Bit is Set

#include <stdio.h>

int isKthBitSet(int n, int k) {
    int tmp;
    tmp = n & (1 << k);
    return (tmp >> k) & 1;
}

int main() {
    int n, k;
    scanf("%d %d", &n, &k);
    printf("%d", isKthBitSet(n, k));
    return 0;
}

We can check bit value at the Kth position by using AND operator with a bitmask at the k-th bit.