Represent the fraction of two numbers in the string format

03 Sep, 2021
Given two integers representing the Numerator and Denominator of a fraction, return the fraction in string format. If the fractional part is repeating, enclose the repeating part in parentheses.
Examples: 
Input: Numerator = 1, Denominator = 2
Output: "0.5"
1/2 = 0.5 with no repeating part.

Input: Numerator = 50, Denominator = 22
Output: "2.(27)"
50/22 = 2.27272727... Since fractional part (27) 
is repeating, it is enclosed in parentheses.
Prerequisites: Recurring Sequence in a Fraction
Approach: The idea is to first calculate the integral quotient (absolute part before decimal point) and then calculate the fractional part. To check if the fractional part is repeating, insert the remainder (numerator % denominator) in a map with key as remainder and value as the index position at which this remainder occurs. If at any point of time, the remainder becomes zero, then there doesn’t exist a repeating fraction otherwise if the remainder is already found in the map, then there exists a repeating fraction.
Below is the implementation of above approach.  
C++
Java
Python3
Javascript
// C++ program to calculate// fraction of two numbers#include <bits/stdc++.h>using namespace std; // Function to return the required fraction// in string formatstring calculateFraction(int num, int den){    // If the numerator is zero, answer is 0    if (num == 0)        return "0";     // If any one (out of numerator and denominator)    // is -ve, sign of resultant answer -ve.    int sign = (num < 0) ^ (den < 0) ? -1 : 1;     num = abs(num);    den = abs(den);     // Calculate the absolute part    // (before decimal point).    int initial = num / den;     // Output string to store the answer    string res;     // Append sign    if (sign == -1)        res += "-";     // Append the initial part    res += to_string(initial);     // If completely divisible, return answer.    if (num % den == 0)        return res;     res += ".";     // Initialize Remainder    int rem = num % den;    map<int, int> mp;     // Position at which fraction starts repeating    // if it exists    int index;    bool repeating = false;    while (rem > 0 && !repeating) {         // If this remainder is already seen,        // then there exists a repeating fraction.        if (mp.find(rem) != mp.end()) {             // Index to insert parentheses            index = mp[rem];            repeating = true;            break;        }        else            mp[rem] = res.size();         rem = rem * 10;         // Calculate quotient, append        // it to result and        // calculate next remainder        int temp = rem / den;        res += to_string(temp);        rem = rem % den;    }     // If repeating fraction exists,    // insert parentheses.    if (repeating) {        res += ")";        res.insert(index, "(");    }     // Return result.    return res;} // Drivers Codeint main(){    int num = 50, den = 22;    cout << calculateFraction(num, den) << endl;     num = -1, den = 2;    cout << calculateFraction(num, den) << endl;    return 0;}
// Java program to calculate fraction// of two numbersimport java.util.*; class GFG {     // Function to return the required fraction    // in string format     public static String calculateFraction(int num, int den)    {        if (num == 0)            return "0"; // if numerator is zero        if (den == 0)            return ""; // if denominator is zero         // result StringBuilder         StringBuilder result = new StringBuilder();        if ((num < 0) ^ (den < 0))            result.append("-"); // check -ve sign         // absolute values of num and den         num = Math.abs(num);        den = Math.abs(den);         long quo = num / den; // Quotient        long rem = num % den * 10; // calculating remainder         result.append(            String.valueOf(quo)); // appending quotient        if (rem == 0)            return result                .toString(); // return if remainder is 0         // if remainder is not zero, continue         result.append(".");        Map<Long, Integer> m            = new HashMap<>(); // map for storing remainder                               // and the indexes of the                               // appropriate decimal in                               // stringbuilder         while (rem != 0) {             if (m.containsKey(rem)) {                 // if the rem is already present, find the                // index and append ( )                 int index = m.get(rem);                String part1 = result.substring(0, index);                String part2 = "("                               + result.substring(                                   index, result.length())                               + ")";                return part1 + part2;            }             // continue updating the map and appending quo            // which was generated by dividing rem with den             m.put(rem, result.length());            quo = rem / den;            result.append(String.valueOf(quo));             // update rem            rem = (rem % den) * 10;        }        return result.toString();    }     // Driver code    public static void main(String[] args)    {        int num = 113;        int den = 56;         String resString1 = calculateFraction(num, den);         num = -1;        den = 2;         String resString2 = calculateFraction(num, den);         System.out.println(resString1);        System.out.println(resString2);    }} // This code is contributed by Saiteja Marisetti
# Python3 program to calculate fraction# of two numbers # Function to return the required# fraction in string formatdef calculateFraction(num, den) :     # If the numerator is zero, answer is 0    if (num == 0):        return "0"     # If any one (out of numerator and denominator)    # is -ve, sign of resultant answer -ve.    sign = -1 if (num < 0) ^ (den < 0) else 1     num = abs(num)    den = abs(den)     # Calculate the absolute part    # (before decimal point).    initial = num // den     # Output string to store the answer    res = ""     # Append sign    if (sign == -1):        res += "-"     # Append the initial part    res += str(initial)     # If completely divisible, return answer.    if (num % den == 0):        return res     res += "."     # Initialize Remainder    rem = num % den    mp = {}     # Position at which fraction starts    # repeating if it exists    index = 0    repeating = False    while (rem > 0 and not repeating) :         # If this remainder is already seen,        # then there exists a repeating fraction.        if ( rem in mp):             # Index to insert parentheses            index = mp[rem]            repeating = True            break                 else:            mp[rem] = len(res)         rem = rem * 10         # Calculate quotient, append it to result        # and calculate next remainder        temp = rem // den        res += str(temp )        rem = rem % den         # If repeating fraction exists,    # insert parentheses.    if (repeating) :        res += ")"        x = res[:index]        x += "("        x += res[index:]        res = x         # Return result.    return res # Driver codeif __name__ =="__main__":    num = 50    den = 22    print(calculateFraction(num, den))    num = -1    den = 2    print(calculateFraction(num, den)) # This code is contributed# Shubham Singh(SHUBHAMSINGH10)
<script> // JavaScript program to calculate// fraction of two numbers // Function to return the required fraction// in string formatfunction calculateFraction(num, den){    // If the numerator is zero, answer is 0    if (num == 0)        return "0";     // If any one (out of numerator and denominator)    // is -ve, sign of resultant answer -ve.    var sign = (num < 0) ^ (den < 0) ? -1 : 1;     num = Math.abs(num);    den = Math.abs(den);     // Calculate the absolute part    // (before decimal point).    var initial = parseInt(num / den);     // Output string to store the answer    var res = [];     // Append sign    if (sign == -1)        res.push("-");     // Append the initial part    res.push(initial.toString());     // If completely divisible, return answer.    if (num % den == 0)        return res;     res.push(".");     // Initialize Remainder    var rem = num % den;    var mp = new Map();     // Position at which fraction starts repeating    // if it exists    var index;    var repeating = false;    while (rem > 0 && !repeating) {         // If this remainder is already seen,        // then there exists a repeating fraction.        if (mp.has(rem)) {             // Index to insert parentheses            index = mp.get(rem);            repeating = true;            break;        }        else            mp.set(rem, res.length);         rem = rem * 10;         // Calculate quotient, append        // it to result and        // calculate next remainder        var temp = parseInt(rem / den);        res.push(temp.toString());        rem = rem % den;    }     // If repeating fraction exists,    // insert parentheses.    if (repeating) {        res.push(")");        res.splice(index,0, "(");    }     // Return result.    return res.join('');} // Drivers Codevar num = 50, den = 22;document.write( calculateFraction(num, den) + "<br>");num = -1, den = 2;document.write( calculateFraction(num, den));  </script>
2.(27)
-0.5
 
SHUBHAMSINGH10
Akanksha_Rai
hitheshkumarcm33309
SaiTejaMarisetti
rrrtnx
anikakapoor
Fraction
Java-HashMap
Mathematical
Mathematical
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