How to convert given number to a character array - GeeksforGeeks

05 Jul, 2021
Given an integer number N, the task is to convert it into a character array.
Example:  
Input: N = 2020 Output: {2, 0, 2, 0} Explanation: Here char array arr[] = {2, 0, 2, 0}Input: N = 12349 Output: {1, 2, 3, 4, 9} Explanation: Here char array arr[] = {1, 2, 3, 4, 9}
Approach:  The basic approach to do this, is to recursively find all the digits of N, and insert it into the required character array. 
Count total digits in the number.Declare a char array of size digits in the number.Separating integer into digits and accommodate it to a character array.Add ASCII value of character ‘0’ is 48 in each element of the array.
Count total digits in the number.
Declare a char array of size digits in the number.
Separating integer into digits and accommodate it to a character array.
Add ASCII value of character ‘0’ is 48 in each element of the array.
Below is the implementation of the above approach:
C
Java
Python3
C#
Javascript
// C program to convert integer// number into character array #include <stdio.h>#include <stdlib.h> // Function to convert integer to// character arraychar* convertIntegerToChar(int N){     // Count digits in number N    int m = N;    int digit = 0;    while (m) {         // Increment number of digits        digit++;         // Truncate the last        // digit from the number        m /= 10;    }     // Declare char array for result    char* arr;     // Declare duplicate char array    char arr1[digit];     // Memory allocation of array    arr = (char*)malloc(digit);     // Separating integer into digits and    // accommodate it to character array    int index = 0;    while (N) {         // Separate last digit from        // the number and add ASCII        // value of character '0' is 48        arr1[++index] = N % 10 + '0';         // Truncate the last        // digit from the number        N /= 10;    }     // Reverse the array for result    int i;    for (i = 0; i < index; i++) {        arr[i] = arr1[index - i];    }     // Char array truncate by null    arr[i] = '\0';     // Return char array    return (char*)arr;} // Driver Codeint main(){     // Given number    int N = 12349;    int len = 5;     // Function call    char* arr = convertIntegerToChar(N);     // Print char array    for (int i = 0; i < len; i++)        printf("%c, ", arr[i]);     return 0;}
// Java program to convert integer// number into character arrayclass GFG{     // Function to convert integer to// character arraystatic char[] convertIntegerToChar(int N){     // Count digits in number N    int m = N;    int digit = 0;         while (m > 0)    {                 // Increment number of digits        digit++;         // Truncate the last        // digit from the number        m /= 10;    }     // Declare char array for result    char[] arr;     // Declare duplicate char array    char []arr1 = new char[digit + 1];     // Memory allocation of array    arr = new char[digit];     // Separating integer into digits and    // accommodate it to character array    int index = 0;         while (N > 0)    {                 // Separate last digit from        // the number and add ASCII        // value of character '0' is 48        arr1[++index] = (char)(N % 10 + '0');         // Truncate the last        // digit from the number        N /= 10;    }     // Reverse the array for result    int i;    for(i = 0; i < index; i++)    {        arr[i] = arr1[index - i];    }     // Return char array    return (char[])arr;} // Driver Codepublic static void main(String[] args){         // Given number    int N = 12349;    int len = 5;     // Function call    char[] arr = convertIntegerToChar(N);     // Print char array    for(int i = 0; i < len; i++)        System.out.printf("%c, ", arr[i]);}} // This code is contributed by amal kumar choubey
# Python3 program to convert integer# number into character array # Function to convert integer to# character arraydef convertIntegerToChar(N):     # Count digits in number N    m = N;    digit = 0;     while (m > 0):         # Increment number of digits        digit += 1;         # Truncate the last        # digit from the number        m /= 10;        # Declare char array for result    arr = ['0' for i in range(digit)]     # Declare duplicate char array    arr1 = ['0' for i in range(digit + 1)];     # Separating integer    # into digits and    # accommodate it    # to character array    index = 0;     while (N > 0):        index += 1;         # Separate last digit from        # the number and add ASCII        # value of character '0' is 48        arr1[index] = chr(int(N % 10 + 48));                # Truncate the last        # digit from the number        N = N // 10;        # Reverse the array for result    for i in range(0, index):        arr[i] = arr1[index - i];        # Return char array    return arr; # Driver Codeif __name__ == '__main__':     # Given number    N = 12349;    len = 5;     # Function call    arr = convertIntegerToChar(N);     # Print array    for i in range(0, len, 1):        print(arr[i], end = " "); # This code is contributed by gauravrajput1
// C# program to convert integer// number into character arrayusing System; class GFG{     // Function to convert integer to// character arraystatic char[] convertintToChar(int N){     // Count digits in number N    int m = N;    int digit = 0;         while (m > 0)    {                 // Increment number of digits        digit++;         // Truncate the last        // digit from the number        m /= 10;    }     // Declare char array for result    char[] arr;     // Declare duplicate char array    char []arr1 = new char[digit + 1];     // Memory allocation of array    arr = new char[digit];     // Separating integer into digits and    // accommodate it to character array    int index = 0;         while (N > 0)    {                 // Separate last digit from        // the number and add ASCII        // value of character '0' is 48        arr1[++index] = (char)(N % 10 + '0');         // Truncate the last        // digit from the number        N /= 10;    }     // Reverse the array for result    int i;    for(i = 0; i < index; i++)    {        arr[i] = arr1[index - i];    }     // Return char array    return (char[])arr;} // Driver Codepublic static void Main(String[] args){         // Given number    int N = 12349;    int len = 5;     // Function call    char[] arr = convertintToChar(N);     // Print char array    for(int i = 0; i < len; i++)        Console.Write("{0}, ", arr[i]);}} // This code is contributed by amal kumar choubey
<script>    // Javascript program to convert integer    // number into character array         // Function to convert integer to    // character array    function convertIntegerToChar(N)    {         // Count digits in number N        let m = N;        let digit = 0;         while (m > 0)        {             // Increment number of digits            digit++;             // Truncate the last            // digit from the number            m = parseInt(m / 10, 10);        }         // Declare char array for result        let arr;         // Declare duplicate char array        let arr1 = new Array(digit + 1);         // Memory allocation of array        arr = new Array(digit);         // Separating integer into digits and        // accommodate it to character array        let index = 0;         while (N > 0)        {             // Separate last digit from            // the number and add ASCII            // value of character '0' is 48            arr1[++index] = String.fromCharCode(N % 10 + '0'.charCodeAt());             // Truncate the last            // digit from the number            N = parseInt(N / 10, 10);        }         // Reverse the array for result        let i;        for(i = 0; i < index; i++)        {            arr[i] = arr1[index - i];        }         // Return char array        return arr;    }         // Given number    let N = 12349;    let len = 5;      // Function call    let arr = convertIntegerToChar(N);      // Print char array    for(let i = 0; i < len; i++)        document.write(arr[i] + ", "); // This code is contributed by divyeshtsbsdiya07</script>
1, 2, 3, 4, 9,
 
Amal Kumar Choubey
GauravRajput1
divyeshrabadiya07
clintra
as5853535
number-digits
Arrays
Mathematical
Strings
Arrays
Strings
Mathematical
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.
Maximum and minimum of an array using minimum number of comparisons
Top 50 Array Coding Problems for Interviews
Stack Data Structure (Introduction and Program)
Introduction to Arrays
Multidimensional Arrays in Java
Program for Fibonacci numbers
C++ Data Types
Write a program to print all permutations of a given string
Set in C++ Standard Template Library (STL)
Coin Change | DP-7