Basic
Practice Problems based on chapter which you learn in previous Tutorials.
1. Sum of Natural Number using Recursion in C++
#include <iostream>
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int
main
() {
double
num1, num2;
std::cout
<< "Enter the first number: ";
std::cin
>> num1;
std::cout
<< "Enter the second number: ";
std::cin
>> num2;
double
sum = num1 + num2;
std::cout
<< "Sum: " << sum << std::endl;
return
0;
}
2. Prime Numbers using Functions
#include <iostream>
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bool
isPrime
(
int
n) {
if
(n <= 1) {
return
false;
}
for
(
int
i = 2; i <=
sqrt
(n); ++i) {
if
(n % i == 0) {
return
false;
}
}
return
true;
}
int
main
() {
int
number;
std::cout
<< "Enter an integer: ";
std::cin
>> number;
if
(
isPrime
(number)) {
std::cout
<< number << " is a prime number." << std::endl;
}
else
{
std::cout
<< number << " is not a prime number." << std::endl;
}
return
0;
}
3. Greatest common Divisor(GCD) using Recursion
#include <iostream>
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int
gcd
(
int
a,
int
b) {
if
(b == 0) {
return
a;
}
else
{
return
gcd
(b, a % b);
}
}
int
main
() {
int
num1, num2;
std::cout
<< "Enter the first integer: ";
std::cin
>> num1;
std::cout
<< "Enter the second integer: ";
std::cin
>> num2;
if
(num1 < 0 || num2 < 0) {
std::cout
<< "Please enter non-negative integers." << std::endl;
return
1;
}
int
result =
gcd
(num1, num2);
std::cout
<< "GCD of " << num1 << " and " << num2 << " is: " << result << std::endl;
return
0;
}
The gcd function is defined to calculate the GCD using the
Euclidean
algorithm and
recursion
.
4. Octal to Decimal
#include <iostream>
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int
octalToDecimal
(
int
octalNumber) {
while
(octalNumber != 0) {
int
remainder = octalNumber % 10;
decimalNumber
+= remainder *
pow
(8, i);
++i;
octalNumber
/= 10;
}
return
decimalNumber;
}
int
main
() {
int
octalNumber;
std::cout
<< "Enter an octal number: ";
std::cin
>> octalNumber;
if
(octalNumber < 0) {
std::cout
<< "Please enter a non-negative octal number." << std::endl;
return
1;
}
int
decimalEquivalent =
octalToDecimal
(octalNumber);
std::cout
<< "Decimal equivalent: " << decimalEquivalent << std::endl;
return
0;
}