Related Articles
Find the conjugate of a Complex number
• Last Updated : 27 Aug, 2020

Given a complex number str in the form of a string, the task is to determine the conjugate of this complex number.
Examples:

Input: str = "3 - 4i"
Output: 3 + 4i

Input: str = "6 - 5i"
Output: 6 + 5i

Approach: A complex number is said to be a conjugate of another complex number if only the sign of the imaginary part of the two numbers is different.

If complex number = x + iy

Conjugate of this complex number = x - iy

Below is the implementation of the above approach :

## C++

 // C++ implementation to Find the// conjugate of a complex number#include using namespace std;  // Function to find conjugate// of a complex numbervoid solve(string s){    string z = s;    int l = s.length();    int i;      if (s.find('+') < l) {          // store index of '+'        i = s.find('+');          replace(s.begin(),                s.end(),                '+', '-');    }    else {          // store index of '-'        i = s.find('-');          replace(s.begin(),                s.end(),                '-', '+');    }      // print the result    cout << "Conjugate of "         << z << " = "         << s << endl;}  // Driver codeint main(){      // initialise the complex number    string s = "3-4i";      solve(s);      return 0;}

## Java

 // Java implementation to Find the// conjugate of a complex number  class GFG{    // Function to find conjugate    // of a complex number    static void solve(String s)    {        String z = s;        int l = s.length();        int i;        String str;          if (s.indexOf('+') != -1) {                   // store index of '+'            i = s.indexOf('+');                   str = s.replace('+', '-');        }        else {                   // store index of '-'            i = s.indexOf('-');                   str = s.replace('-', '+');        }               // print the result        System.out.println("Conjugate of "             + z + " = "             + str);    }           // Driver code    public static void main(String []args)    {               // initialise the complex number        String s = "3-4i";               solve(s);    }}  // This code is contributed by chitranayal

## Python3

 # Python3 implementation to Find the # conjugate of a complex number   # Function to find conjugate # of a complex number def solve(s):    z = s    l = len(s)     i = 0    if (s.find('+') != -1):            # store index of '+'         i = s.find('+')            s = s.replace('+', '-')    else:        # store index of '-'         i = s.find('-')          s = s.replace('-', '+',1)        # print the result     print("Conjugate of ",z," = ",s)    # Driver code   # initialise the complex number s = "3-4i"solve(s)  # This code is contributed by Sanjit_Prasad

## C#

 // C# implementation to find the// conjugate of a complex numberusing System;  class GFG{      // Function to find conjugate// of a complex numberstatic void solve(String s){    String z = s;    int l = s.Length;    int i;    String str;      if (s.IndexOf('+') != -1)     {                  // Store index of '+'        i = s.IndexOf('+');          str = s.Replace('+', '-');    }    else     {          // Store index of '-'        i = s.IndexOf('-');          str = s.Replace('-', '+');    }      // print the result    Console.WriteLine("Conjugate of "+ z +                      " = " + str);}  // Driver codepublic static void Main(String []args){      // Initialise the complex number    String s = "3-4i";      solve(s);}}  // This code is contributed by amal kumar choubey
Output:
Conjugate of 3-4i = 3+4i

Attention reader! Don’t stop learning now. Get hold of all the important mathematical concepts for competitive programming with the Essential Maths for CP Course at a student-friendly price. To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.

My Personal Notes arrow_drop_up