C++ coding tasks are commonly requested during interviews. These tasks may cover fundamental concepts as well as topics like arrays, strings, pointers, linked lists, file handling, and more. Now, let's explore a compilation of key C++ programs.
1) Fibonacci Series
To generate the Fibonacci series in C++, we can create two separate programs - one using recursion and the other without using recursion.
- Fibonacci Series without Recursion:
#include <iostream>
using namespace std;
int main() {
int n, first = 0, second = 1, next;
cout << "Enter the number of terms: ";
cin >> n;
cout << "Fibonacci Series: ";
for (int i = 0; i < n; i++) {
if (i <= 1)
next = i;
else {
next = first + second;
first = second;
second = next;
}
cout << next << " ";
}
return 0;
}
- Fibonacci Series using Recursion:
#include <iostream>
using namespace std;
int fibonacci(int n) {
if (n <= 1)
return n;
return fibonacci(n - 1) + fibonacci(n - 2);
}
int main() {
int terms;
cout << "Enter the number of terms: ";
cin >> terms;
cout << "Fibonacci Series: ";
for (int i = 0; i < terms; i++) {
cout << fibonacci(i) << " ";
}
return 0;
}
Input: 10
Output: 0 1 1 2 3 5 8 13 21 34
2) Prime number
Write a c++ program to check prime number.
Input: 17
Output: not prime number
Input: 57
Output: prime number
3) Palindrome number
Write a c++ program to check palindrome number.
Input: 121
Output: not palindrome number
Input: 113
Output: palindrome number
4) Factorial
Create a C++ program that calculates and displays the factorial of a given number.
Input: 5
Output: 120
Input: 6
Output: 720
5) Armstrong number
Write a c++ program to check armstrong number.
Input: 371
Output: armstrong
Input: 342
Output: not armstrong
6) Sum of Digits
Write a c++ program to print sum of digits.
Input: 23
Output: 5
Input: 624
Output: 12
7) Reverse Number
Write a c++ program to reverse given number.
Input: 234
Output: 432
8) Swap two numbers without using third variable
Create a C++ program to exchange the values of two numbers without the need for a third variable.
#include <iostream>
using namespace std;
int main() {
int num1, num2;
cout << "Enter two numbers: ";
cin >> num1 >> num2;
cout << "Before swapping - num1: " << num1 << ", num2: " << num2 << endl;
num1 = num1 + num2;
num2 = num1 - num2;
num1 = num1 - num2;
cout << "After swapping - num1: " << num1 << ", num2: " << num2 << endl;
return 0;
}
Input: a=5 b=10
Output: a=10 b=5
9) Matrix Multiplication
Develop a C++ program to display the multiplication result of two matrices.
Input:
first matrix elements:
1 2 3
1 2 3
1 2 3
second matrix elements
1 1 1
2 1 2
3 2 1
Output:
multiplication of the matrix:
14 9 8
14 9 8
14 9 8
10) Decimal to Binary
Develop a C++ program that converts a decimal number into its binary equivalent.
Here is a sample code snippet to achieve this conversion:
#include <iostream>
using namespace std;
void decimalToBinary(int decimalNum) {
int binaryNum[32];
int i = 0;
while (decimalNum > 0) {
binaryNum[i] = decimalNum % 2;
decimalNum = decimalNum / 2;
i++;
}
for (int j = i - 1; j >= 0; j--) {
cout << binaryNum[j];
}
}
int main() {
int decimalNum;
cout << "Enter a decimal number: ";
cin >> decimalNum;
cout << "Binary equivalent: ";
decimalToBinary(decimalNum);
return 0;
}
In this program, the decimalToBinary function takes a decimal number as input and converts it into binary by repeatedly dividing by 2 and storing the remainders in an array. Finally, the binary equivalent is printed by iterating through the array in reverse order.
Input: 9
Output: 1001
Input: 20
Output: 10100
11) Alphabet Triangle
Write a c++ program to print alphabet triangle.
Output:
A
ABA
ABCBA
ABCDCBA
ABCDEDCBA
12) Number Triangle
Write a c++ program to print number triangle.
Input: 7
Output:
enter the range= 6
1
121
12321
1234321
123454321
12345654321
13) Fibonacci Triangle
Create a C++ program to display a Fibonacci triangle.
Input: 5
Output:
1
1 1
1 1 2
1 1 2 3
1 1 2 3 5
14) Number in Characters
Create a C++ program that converts a number into its equivalent in words.
Input: 74254
Output: Seven Four Two Five Four
Input: 203
Output: two zero three
