Compress Interleaved Bits Reverse Bit Spreading

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

uint8_t compress_bits(uint16_t val) {
    uint8_t output = 0;
    int idx = 0;
    for (int i = 0; i < 16; i+=2){
        char bit = (val >> i) & 0x01;
        output |= bit << idx;
        idx++;
    }
    return output;
}

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

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