Set or Clear a Specific Bit in a Register

Code

#include <stdio.h>

unsigned char modifyBit(unsigned char reg, int pos, int mode) {
    int sam_reg = reg;
    int binary[32];
    int i = 0;
    int k;
    while(sam_reg>0){
        binary[i] = sam_reg % 2;
        sam_reg = sam_reg/2;
        i++;
    } 
    
    if( mode == true){
        binary[(pos-i)-1] = 1;
    }
    else{
        binary[(pos-i)-1] = 0;
    }
    int value= 0;
    for(k = i-1;k<0,k--){
        if(k=true){
            value += 2;
        }
    }
    printf("%d", value);
}

int main() {
    unsigned char reg;
    int pos, mode;
    scanf("%hhu %d %d", &reg, &pos, &mode);
    printf("%d", modifyBit(reg, pos, mode));
    return 0;
}

Solving Approach