Check and Set Bits

Check if Bit is Set and Set/Clear Bits in C++

BeginnerTopic: Bitwise Operations Programs
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C++ Check and Set Bits Program

This program helps you to learn the fundamental structure and syntax of C++ programming.

Try This Code
#include <iostream>
#include <bitset>
using namespace std;

bool isBitSet(int num, int pos) {
    return (num & (1 << pos)) != 0;
}

int setBit(int num, int pos) {
    return num | (1 << pos);
}

int clearBit(int num, int pos) {
    return num & ~(1 << pos);
}

int toggleBit(int num, int pos) {
    return num ^ (1 << pos);
}

int main() {
    int num = 12;  // 00001100
    
    cout << "Original number: " << bitset<8>(num) << " (" << num << ")" << endl;
    
    // Check bits
    cout << "\nChecking bits:" << endl;
    for (int i = 0; i < 8; i++) {
        cout << "Bit " << i << ": " << (isBitSet(num, i) ? "SET" : "CLEAR") << endl;
    }
    
    // Set bit 0
    num = setBit(num, 0);
    cout << "\nAfter setting bit 0: " << bitset<8>(num) << " (" << num << ")" << endl;
    
    // Clear bit 2
    num = clearBit(num, 2);
    cout << "After clearing bit 2: " << bitset<8>(num) << " (" << num << ")" << endl;
    
    // Toggle bit 3
    num = toggleBit(num, 3);
    cout << "After toggling bit 3: " << bitset<8>(num) << " (" << num << ")" << endl;
    
    return 0;
}
Output
Original number: 00001100 (12)

Checking bits:
Bit 0: CLEAR
Bit 1: CLEAR
Bit 2: SET
Bit 3: SET
Bit 4: CLEAR
Bit 5: CLEAR
Bit 6: CLEAR
Bit 7: CLEAR

After setting bit 0: 00001101 (13)
After clearing bit 2: 00001001 (9)
After toggling bit 3: 00000001 (1)

Understanding Check and Set Bits

Check bit: num & (1 << pos). Set bit: num | (1 << pos). Clear bit: num & ~(1 << pos). Toggle bit: num ^ (1 << pos). These operations are fundamental for bit manipulation. Used in flags, permissions, and efficient data structures.

Note: To write and run C++ programs, you need to set up the local environment on your computer. Refer to the complete article Setting up C++ Development Environment. If you do not want to set up the local environment on your computer, you can also use online IDE to write and run your C++ programs.

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