Compress Interleaved Bits Reverse Bit Spreading

Code

#include <stdio.h>
#include <stdint.h>

uint8_t compress_bits(uint16_t val) {
    uint8_t res = 0;
    int in_pos = 0;
    int out_pos = 0;
    while(val>0){
        if(in_pos%2==0){
            res|=(val&1)<<out_pos;
            out_pos++;
        }
        val = val>>2;
        in_pos+=2;

    } 
    return res;
}

int main() {
    uint16_t val;
    scanf("%hu", &val);

    uint8_t result = compress_bits(val);
    printf("%u", result);
    return 0;
}

Solving Approach