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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
#include <stdint.h>

void print_bits(uint8_t byte, char* label) {
    for(int i = 0; i < 8; i++) {
        printf("%d",((byte >> (7 - i)) & 1));
    }
    printf("  # %s\n", label);
}

int main(int argc, char* argv[]) {
    uint8_t n1 = 0xff;  // 11111111₂
    uint8_t n2 = n1 << 1;
    uint8_t n3 = n2 >> 1;

    uint16_t n6 = (n1 << 1);  // like the implicit promotion that the compiler does for you
    uint16_t n7 = (n6 >> 1);
    uint8_t  n8 = n7;         // bits are truncated when assigning back to the smaller type

    uint8_t n9 = (n1 << 1) >> 1;  // BUG

    print_bits(n1, "n1");
    print_bits(n2, "n2");
    print_bits(n3, "n3");
    print_bits(n9, "n9");

    printf("n2 == 0x%02x\n", n2);
    // %02x means int in hex notation, >=2 digits, 0-padded
    
    printf("n3 == 0x%02x\n", n3);
    
    // Set the most signficant (leftmost) bit to zero using << and >>.
    
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

© Copyright 2023 Alexander J. Quinn         This content is protected and may not be shared, uploaded, or distributed.