strlen in string c++ code example

Example 1: strlen in cpp

#include <cstring>
#include <iostream>

using namespace std;

int main()
{
    char str1[] = "This a string";
    
    int len1 = strlen(str1);

    cout << "Length of str1 = " << len1 << endl;

    return 0;
}

Example 2: how to find the length of an string in c++

#include<iostream>
#include<cstring>
using namespace std;
main() {
   string myStr = "This is a sample string";
   char myStrChar[] = "This is a sample string";
   cout << "String length using string::length() function: " << myStr.length() <<endl;
   cout << "String length using string::size() function: " << myStr.size() <<endl;
   cout << "String length using strlen() function for c like string: " << strlen(myStrChar) <<endl;
   cout << "String length using while loop: ";
   char *ch = myStrChar;
   int count = 0;
   while(*ch != '\0'){
      count++;
      ch++;
   }
   cout << count << endl;
   cout << "String length using for loop: ";
   count = 0;
   for(int i = 0; myStrChar[i] != '\0'; i++){
      count++;
   }
   cout << count;
}