﻿ C++ - Second occurrence of a string within another string

# C++ String Exercises: Second occurrence of a string within another string

## C++ String: Exercise-41 with Solution

Write a C++ program that finds the position of the second occurrence of a string in another string. If the substring does not appear at least twice return -1.

Test Data:
("the qu qu", "qu") -> 7
("theququ", "qu") -> 5
("thequ", "qu") -> -1

Sample Solution:

C++ Code:

``````#include <bits/stdc++.h> // Include all standard libraries

using namespace std; // Using the standard namespace

// Function to find the position of the second occurrence of a substring in a string
int test(std::string text, std::string sstr) {
// Find the position of the first occurrence of the substring in the text
// Then, search for the substring from the index after the first occurrence
return text.find(sstr, text.find(sstr) + sstr.size());
}

int main() {
string text = "the qu qu"; // Initialize the input string
string sstr = "qu"; // Initialize the substring to search
cout << "String: " << text; // Display the original string
cout << "\nSubstring: " << sstr; // Display the substring
// Find and display the position of the second occurrence of the substring
cout << "\nPosition of the second occurrence of the said substring: " << test(text, sstr);

text = "theququ"; // Change the input string
sstr = "qu"; // Change the substring to search
cout << "\n\nString: " << text; // Display the modified string
cout << "\nSubstring: " << sstr; // Display the substring
// Find and display the position of the second occurrence of the substring
cout << "\nPosition of the second occurrence of the said substring: " << test(text, sstr);

text = "thequ"; // Change the input string
sstr = "qu"; // Change the substring to search
cout << "\n\nString: " << text; // Display the modified string
cout << "\nSubstring: " << sstr; // Display the substring
// Find and display the position of the second occurrence of the substring
cout << "\nPosition of the second occurrence of the said substring: " << test(text, sstr);
}
``````

Sample Output:

```String: the qu qu
Substring: qu
Position of the second occurrence of the said substring: 7

String: theququ
Substring: qu
Position of the second occurrence of the said substring: 5

String: thequ
Substring: qu
Position of the second occurrence of the said substring: -1
```

Flowchart:

C++ Code Editor:

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