# Convert A String To An Integer ## Write a program to convert a string to an integer ```txt Input : "123" Output : 123 ``` --- ```c #include #include int main() { int num; char word[20]; printf("Enter a string to convert into Integer : "); scanf("%s", word); num = atoi(word); printf("The Integer is : %i", num); return 0; } ``` ```cpp #include using namespace std; int string_to_integer(string str) { return stoi(str); } int main() { string s; cin >> s; cout << string_to_integer(s); return 0; } ``` ```csharp using System; class MainClass { public static void Main (string[] args) { Console.WriteLine(Convert.ToInt16("123")); } } ``` ```fsharp open System let test = "123" let mutable result = 0 if Int32.TryParse(test, &result) then printfn "%A" result else fprintf stderr "Error: Not a number" ``` ```java import java.util.Scanner; public class ConvertAStringToAnInteger { public static void main(String[] args) { Scanner sc = new Scanner(System.in); try{ System.out.print("Enter the string that needs to be converted to INT: "); String string = sc.nextLine(); sc.close(); Integer intVal = Integer.valueOf(string); System.out.print("Value converted is: " + intVal); }catch(Exception e){ System.out.println("Invalid input: " + e); } } } ``` ```javascript // Javascript program to convert a String to an Integer function convertWithUnary(str) { // converts string representations of integers or decimals return +str; } function parseInteger(str, radix = 0) { // radix is an integer between 2 - 36 return parseInt(str, radix); } function floor(str) { return Math.floor(str); } function round(str) { return Math.round(str); } // Examples: console.log(convertWithUnary("2342")); // 2342 console.log(convertWithUnary("234.67")); // 234.67 console.log(Number("1234")); // 1234 - native JS Number Method console.log(~~"1234"); // 1234 - Double Tilde - bitwise negation console.log(parseInteger("321")); // 321 console.log(parseInteger("234.33")); // 234 console.log(parseInteger("6234sadf")); // 6234 - converts numbers in the string untill alphabets/special characters are found console.log(parseInteger("0xD")); // 13 - converts 0xD hexadecimal-base 16 with Decimal base 10 console.log(parseInteger("0xD", 2)); // 0 - converts 0xD hexadecimal with radix 2 console.log(parseInteger("0xD", 36)); // 1201 - converts 0xD hexadecimal with radix 36 console.log(parseInteger("0xD", 42)); // NaN - returns Nan with radix out of range console.log(floor("234.234")); // 234 // rounds down to the integer less than or equal to the given value console.log(floor("234.999")); // 234 // rounds down to the integer less than or equal to the given value console.log(floor("234adf.234")); // NaN // works only on string representations of numbers console.log(round("234.234")); // 234 // rounds to the nearest integer console.log(round("234.999")); // 235 // rounds to the nearest integer console.log(round("234adf.234")); // NaN // works only on string representations of numbers ``` ```kotlin import java.util.Scanner fun main() { val scanner = Scanner(System.`in`) print("Enter the string::") val inputString = scanner.nextLine(); scanner.close(); try { val integer = inputString.toInt(); print("Integer value is::"+integer) } catch(exe:NumberFormatException) { print("Invalid Input") } } ``` ```ruby def stringToNumber(string) num = string.to_i num if num.to_s == string end puts stringToNumber '123' ``` ```swift import Swift import Foundation Int("123") // 123 Int("+123") // 123 Int("-123") // -123 ``` ```typescript const stringToInteger = (str: string): number => { return parseInt(str); }; console.log(stringToInteger("123")); ``` ```julia println("Enter number in string: ") str = readline() int = parse(Int, str) println("String to Integer: ", int) ``` ```scala import scala.io.StdIn._; object stringToInteger { def main(args:Array[String]):Unit={ println("Enter a number in String : "); var n = readLine().toInt; println("String to Integer : "+n); } } ``` ```dart import 'dart:convert'; void stringToInt(String s){ int no = int.parse(s); print(no); } void main() { stringToInt("123"); } ``` ```go package main import ( "fmt" "strconv" ) func StrtoInt(s string) int { //converting string to int num,err:=strconv.Atoi(s) if err!=nil{ fmt.Println(err) } //returing number return num } func main(){ fmt.Printf("Enter a String number:") var s string fmt.Scanf("%v",&s) //printing the output fmt.Println("After converting str to int:",StrtoInt(s)) } ``` ```php ``` ```perl $string = "123"; $num = int($string); print "String to Integer conversion : $num\n"; ``` ```python n = input() number = int(input()) print(number) ``` ```r # Prompt the user for input string_value <- readline(prompt="Enter: ") # Convert the string to an integer integer_value <- as.integer(string_value) # Print the result print(integer_value) ```

Convert A String To An Integer

Write a program to convert a string to an integer

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