Bit Spreading Interleave Bits with Zeros

Code

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

uint16_t spread_bits(uint8_t val) {
    if(val == 0) {
        return 0;
    }
    uint16_t final;
    int i = 0;
    int j = 0;
    while (i < 8 && j < 16) {
        if (val & (1 << i)) {
            final |= (1 << j);
            final &= ~(1 << j + 1);
            i++;
            j += 2;
        } else {
            final &= ~(1 << j);
            final &= ~(1 << j + 1);
            i++;
            j += 2;
        }
    }
    return final;
}

int main() {
    uint8_t val;
    scanf("%hhu", &val);

    uint16_t result = spread_bits(val);
    printf("%u", result);
    return 0;
}

Solving Approach