C++ is one the most popular languages in the programming world. In this article we will be looking towards 10 simple programs for beginners in CPP.
- Adding two numbers in C++.
Ans. Take two variables and take user input and add them.#include <iostream> using namespace std; int main() { int a ; int b ; cin>>a>>b; cout<<a+b; return 0; } Input: 2 5 Output: 7
- Check if a number is even or odd.
Ans. If the given number is divisible by 2 then it is even otherwise odd.#include <iostream> using namespace std; int main() { int a ; cin>>a; if(a%2 == 0) // if remainder is zero then even number cout<<”even”; else cout<<”odd”; return 0; } Input: 8 Output: even
- Write a program to swap two numbers.
Ans. Use a temporary variable to store one of the numbers.#include <iostream> using namespace std; int main() { int a = 10; int b = 20; cout<<a<<" "<<b<<endl; int temp = a; a = b; b = temp; cout<<a<<" "<<b<<endl; return 0; } Output: 10 20 20 10
- Write a program to find the largest number among three numbers.
Ans. A number will be largest if number is greater than both the other numbers.#include <iostream> using namespace std; int main() { float a, b, c; cin >> a >> b >> c; if(a >= b && a >= c) cout << "Largest number: " << a; if(b >= a && b >= c) cout << "Largest number: " << b; if(c >= a && c >= b) cout << "Largest number: " << c; return 0; } Input: 1 2 3 Largest number: 3
- Find the sum of all the natural numbers from 1 to n.
Ans. We can do this using two ways, one is by iterating from 1 to n and adding them up while the other way is using the summation formula –summation of i from 1 to n=n(n+1)/2=1+2+3+4+..+(n-1)+n #include <iostream> using namespace std; int main() { int n, sum = 0; cin >> n; for (int i = 1; i <= n; ++i) { sum += i; } // or sum = n*(n+1)/2; cout << sum; return 0; } Input: 5 Output: 15
- Write a program to check whether a number is prime or not.
Ans. A prime number is not divisible by any number smaller than it except 1. Basically, it has only two factors 1 and itself.#include <iostream> using namespace std; int main() { int a ; cin>>a; int b = 2; //start from b as 1 can divide any number bool prime = true; while(b!=a){ if(a%b == 0) { prime = false; break; } b++; } if(prime) cout<<"prime"; else cout<<"not prime"; return 0; } Output: prime
- Compute the power a given number to a given power.
Ans. We need to keep multiplying the same number power times.3^3=3*3*3=27 #include <iostream> using namespace std; int main() { int power; float base, result = 1; cin >> base >>power; while (power != 0) { result *= base; power--; } cout << result; return 0; } Input: 3 3 Output: 27
- Calculate the average of all the elements present in an array.
Ans.average= summation〖arr[i]〗/n #include <iostream> using namespace std; int main() { int n; cin>>n; int arr[n]; float sum = 0.0; for(int i = 0;i<n;i++) cin>>arr[i]; for(int i = 0;i<n;i++) sum += arr[i]; cout<<(float)(sum/(float)n); return 0; } Input: 3 1 4 5 Output: 3.33333
- Write a program to find the GCD of two numbers.
Ans. GCD is the greatest common divisor of the two numbers.#include <iostream> using namespace std; int gcd(int a,int b){ if(b == 0) return a; return gcd(b,a%b); } int main() { int a ,b ; cin>>a>>b; cout<<gcd(a,b); return 0; } Input: 35 25 Output: 5
- Write a function to find the length of a string in CPP.
Ans. Iterate through the string and increase count by 1 till we reach the end of the string.#include <iostream> using namespace std; int main() { string str; cin>>str; int count = 0; for(int i = 0;str[i];i++) // till the string character is null count++; cout<<count; } Input: abcde Output: 5
This article tried to discuss Simple C++ programs for beginners. Hope this blog helps you understand the concept. To practice more problems you can check out MYCODE | Competitive Programming.
very helpful for beginners