#include <stdio.h>
#include <stdint.h>
uint8_t reverse_bits(uint8_t val) {
// reverse nibbles
val = ((val & 0xF0) >> 4) | ((val & 0x0F) << 4);
// reverse 2 bits
val = ((val & 0xCC) >> 2) | ((val & 0x33) << 2);
// reverse individual bits
val = ((val & 0xAA) >> 1) | ((val & 0x55) << 1);
return val;
}
int main() {
uint8_t val;
scanf("%hhu", &val);
uint8_t result = reverse_bits(val);
printf("%u", result);
return 0;
}
/*
i = 0001 1010
o = 0101 1000
swap nibbles (4 bytes) (mask = 0xF0 for left nibble and 0x0F for right nibble)
1010 0001
swap 2 bits (mask = 0b1100 1100 (0xCC) for left sides and 0b0011 0011 (0x33) for right sides)
1010 0100
swap 1 bits (mask = 0b1010 1010 (0xAA) for left sides and 0b0101 0101 (0x55) for right sides)
0101 1000
*/
Input
26
Expected Output
88