C++ Exercises: Check a given array of integers and return true if there are two values 15, 15 next to each other

Last update on August 12 2025 12:51:13 (UTC/GMT +8 hours)

Compare Strings for Same Length 2 Substrings

Write a C++ program to compare two given strings and return the number of positions where they contain the same length 2 substring.

Sample Input:
{ 5, 5, 1, 15, 15 }
{ 15, 2, 3, 4, 15 }
{ 3, 3, 15, 15, 5, 5}
{ 1, 5, 15, 7, 8, 15}

Sample Solution:

C++ Code :

#include <iostream>
using namespace std;

// Function to check if the array contains consecutive occurrences of number 15
static bool test(int numbers[], int arr_length)
{
    // Loop through the array elements (except the last one) to find consecutive occurrences of 15
    for (int i = 0; i < arr_length - 1; i++)
    {
        // Check if the current element and the next element are both equal to 15
        if (numbers[i + 1] == numbers[i] && numbers[i] == 15)
            return true; // Return true if two consecutive elements are equal to 15
    }
    return false; // Return false if no consecutive occurrences of 15 are found
}

int main() 
{  
    // Test cases with different arrays
    int nums1[] = {5, 5, 1, 15, 15}; // Array 1
    int arr_length = sizeof(nums1) / sizeof(nums1[0]); // Calculate the length of array 1
    cout << test(nums1, arr_length) << endl; // Check if array 1 contains consecutive occurrences of 15

    int nums2[] = {15, 2, 3, 4, 15}; // Array 2
    arr_length = sizeof(nums2) / sizeof(nums2[0]); // Calculate the length of array 2
    cout << test(nums2, arr_length) << endl; // Check if array 2 contains consecutive occurrences of 15

    int nums3[] = {3, 3, 15, 15, 5, 5}; // Array 3
    arr_length = sizeof(nums3) / sizeof(nums3[0]); // Calculate the length of array 3
    cout << test(nums3, arr_length) << endl; // Check if array 3 contains consecutive occurrences of 15

    int nums4[] = {1, 5, 15, 7, 8, 15}; // Array 4
    arr_length = sizeof(nums4) / sizeof(nums4[0]); // Calculate the length of array 4
    cout << test(nums4, arr_length) << endl; // Check if array 4 contains consecutive occurrences of 15

    return 0; // Return 0 to indicate successful completion
}

Sample Output:

1
0
1
0

Visual Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a C++ program to compare two strings and count the positions where both have identical substrings of length 2.
• Write a C++ program that reads two strings and outputs the number of matching two-character sequences starting at the same positions.
• Write a C++ program to compare two input strings and return the total count of overlapping length-2 substrings that are the same.
• Write a C++ program that iterates through two strings concurrently and counts how many times a substring of length 2 matches at the same index in both.

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