Binary Number is expressed in base 2. It uses only two digits ‘0’ and ‘1’. Each digit in a binary number is a bit.
Sample binary Number − 0100010111
1’s Complement
One's complement of a binary number is obtained by reversing the digits of the binary number i.e. transforming 1 with 0 and 0 with 1.
Example
1’s Complement of 101100 = 010011
2’s Complement
Two’s complement of a binary number is obtained by adding one to the one’s complement of a binary number i.e. 1’s complement + 1.
Example
2’s complement of 101101 is 010011.
Example Code
Code to find One’s and two’s complement −
#include <iostream> #include<string.h> using namespace std; int main() { char binary[10] = "01001011"; cout<<“Binary number is ”<<binary; //once complement.... int length = strlen(binary); for(int i=0;i<length;i++) { if(binary[i] == '0') { binary[i]= '1'; } else binary[i] = '0'; } cout<<“One’s Complement is ”<<binary<<endl; // cout<<binary[length-1]; for(int i = length-1; i>=0; i--) { // cout<<binary[i]; if(binary[i] == '0') { binary[i] = '1'; //cout<<binary[i]; break; } else { binary[i] = '0'; } } cout<<“Two’s complement is ”<<binary; return 0; }
Output
Binary number is 01001011 One’s complement is 10110100 Two’s complement is 10110101