C++ Exercises: Create a new string of length 2 starting at the given index of a given string

Last update on April 07 2025 12:57:53 (UTC/GMT +8 hours)

String of Length 2 Starting at Given Index

Write a C++ program to create a string of length 2 starting at the given index of a given string.

Sample Solution:

C++ Code :

#include <iostream> // Including the input/output stream library

using namespace std; // Using the standard namespace

// Function that extracts a substring of length 2 from the given index in the input string
string test(string s1, int index)
{
    // Conditional operator to check if index+2 is within the length of the string
    return index + 2 <= s1.length() ? s1.substr(index, 2) : s1.substr(0, 2);
    // Return a substring starting from the given index of length 2 if possible, otherwise return the first two characters of s1
}

// Main function
int main() 
{
    cout << test("Hello", 1) << endl;   // Output the result of test function with "Hello" and index=1
    cout << test("Python", 2) << endl;  // Output the result of test function with "Python" and index=2
    cout << test("on", 1) << endl;      // Output the result of test function with "on" and index=1
    return 0;    // Return statement indicating successful termination of the program
}

Sample Output:

el
th
on

Visual Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a C++ program to extract a substring of length 2 starting from a specified index in a given string.
• Write a C++ program that reads a string and an index, then outputs a substring of exactly 2 characters beginning at that index.
• Write a C++ program to form and print a new string containing 2 consecutive characters from an input string starting at a user-defined position.
• Write a C++ program that takes a string and a starting index, then extracts and displays a 2-character substring from that position.

C++ Code Editor:

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