std::to_string in C++

It is one of the method to convert the value’s into string.

The others are-

By using stringstream class
By using to_string() method
By using boost.lexical cast

The to_string() method takes a single integer variable or other data type and converts into the string.

Convert numerical value to string Syntax :

string to_string (int val);
string to_string (long val);
string to_string (long long val);
string to_string (unsigned val);
string to_string (unsigned long val);
string to_string (unsigned long long val);
string to_string (float val);
string to_string (double val);
string to_string (long double val);

Parameters :
val - Numerical value.

Return Value :
A string object containing the representation of val as a sequence of characters.

CPP

// CPP program to illustrate
// std::to_string
#include <bits/stdc++.h>

// Driver code
int main()
{
    int var1=16;

    // Converting float to string
    std::string str1 = std::to_string(12.10);

    // Converting integer to string
    std::string str2 = std::to_string(9999);

    // Converting integer to string by taking a variable
    std::string str3 = std::to_string(var1);

    // Printing the strings
    std::cout << str1 << '\n';
    std::cout << str2 << '\n';
      std::cout << str3 << '\n';
    return 0;
}

Output

12.100000
9999
16

Problem : Find a specific digit in a given integer. Example :

Input : number  = 10340, digit = 3
Output : 3 is at position 3

Implementation:

CPP

// CPP code to find a digit in a number
// using std::tostring
#include <bits/stdc++.h>

// Driver code
int main()
{

    // Converting number to string
    std::string str = std::to_string(9954);

    // Finding 5 in the number
    std::cout << "5 is at position " << str.find('5') + 1;
}

Output :

5 is at position 3