C++ Exercises: Create a new string using first two characters of a given string

Last update on April 07 2025 12:56:39 (UTC/GMT +8 hours)

First Two Characters or Full String if Less Than 2

Write a C++ program to create a new string using the first two characters of a given string. If the string length is less than 2, return the original string.

Sample Solution:

C++ Code :

#include <iostream>
using namespace std;

// Function 'test' returns the first two characters of the input string if its length is 2 or more
// Otherwise, it returns the entire input string
string test(string s1)
{
    // Checks if the length of the input string is less than 2
    if (s1.length() < 2)
    {
        // Returns the input string 's1' if its length is less than 2
        return s1;
    }
    else
    {
        // Returns the first two characters of the input string 's1'
        return s1.substr(0, 2);
    }
}

// Main function to test the 'test' function
int main() 
{
    // Displays the output of the 'test' function for different string inputs
    cout << test("Hello") << endl;  // Output: "He" (first two characters of "Hello")
    cout << test("Hi") << endl;     // Output: "Hi" (entire string as length is 2)
    cout << test("H") << endl;      // Output: "H" (entire string as length is less than 2)
    cout << test(" ") << endl;      // Output: " " (entire string as length is less than 2)
    return 0;    
}

Sample Output:

He
Hi
H

Visual Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a C++ program to output the first two characters of a string, or the entire string if its length is less than two.
• Write a C++ program that reads a string and prints its first two letters; if the string is too short, print it as is.
• Write a C++ program to extract and display the first two characters of an input string, with a condition for short strings.
• Write a C++ program that checks the length of a string and, if it is under two characters, outputs the full string; otherwise, outputs the first two characters.

C++ Code Editor:

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