// Code: Common Functions (C++) // Author: Cool Codin // These functions are the most common functions which are used in day - to - day programs // I have divided it into suitable sections, so that you can use these in your own projects :) // I didn't use 'using namespace std' because it can cause confusion in namespaces // Version: 1.1 /* Update Log: 1.1: - More Math Functions 1.2: - Use of Function Overloading instead of separate functions - Added a Math Function */ // ---------------------------------------------------------------------------------------------------- \\ /* .h file */ // #pragma once #include #include #include #include #include class CommonFunctions { public: CommonFunctions(); int factorial(int number); int nk(int n, int k); int abN(int a, int b, int n); int _abN(int a, int b, int n); int sumArr(int arr[], int size); float sumArr(float arr[], int size); double sumArr(double arr[], int size); int sumFirst(int range); bool isPrime(int number); bool isPalindrome(std::string str); bool isVowel(char letter); std::string password(int length); }; // ---------------------------------------------------------------------------------------------------- \\ /* .cpp file */ // #include "func.h" // Constructor CommonFunctions::CommonFunctions() { std::cout << "Welcome to my program ;)" << std::endl; std::cout << std::endl; } // number * (number - 1) * ... * 2 * 1 int CommonFunctions::factorial(int number) { if (number == 0 || number == 1) return 1; else if (number > 1) return number * factorial(number - 1); else return 0; } // n! / k! * (n - k)! where ! represents factorial int CommonFunctions::nk(int n, int k) { try { int C = this->factorial(n) / (this->factorial(k) * this->factorial(n - k)); return C; } catch (int C) { return 0; } } // (a + b) ^ n int CommonFunctions::abN(int a, int b, int n) { int sum = 0; for (int i = 0; i <= n; i++) sum += (this->nk(n, i)) * (pow(a, (n - i))) * (pow(b, i)); return sum; } // (a - b) ^ n int CommonFunctions::_abN(int a, int b, int n) { int sum = 0; for (int i = 0; i <= n; i++) sum += (this->nk(n, i)) * (pow(a, (n - i))) * (pow(-b, i)); return sum; } // { 3 + 4 + 5 + 6 + 10 } int CommonFunctions::sumArr(int arr[], int size) { int sum = 0; for (int i = 0; i < size; i++) sum += arr[i]; return sum; } // { 1.1 + 2.2 + 3.3 + 4.4 + 5.5 } float CommonFunctions::sumArr(float arr[], int size) { float sum = 0.0f; for (int i = 0; i < size; i++) sum += arr[i]; return sum; } // { 1.11111 + 2.22222 + 3.33333 + 4.44444 + 5.55555 } double CommonFunctions::sumArr(double arr[], int size) { double sum = 0.0; for (int i = 0; i < size; i++) sum += arr[i]; return sum; } // { 1 + 2 + 3 + ... + (range - 1) + range } int CommonFunctions::sumFirst(int range) { int sum = 0; for (int i = 1; i <= range; i++) sum += i; return sum; } // to check if number is prime bool CommonFunctions::isPrime(int number) { if (number < 2) return false; else if (number > 2) for (int i = 2; i < number; i++) if (number % i == 0) return false; return true; } // To check if str = rts bool CommonFunctions::isPalindrome(std::string str) { std::string reverse = ""; for (int i = str.length() - 1; i >= 0; i--) reverse += str[i]; return str == reverse; } // To check if letter = a, e, i, o, u, A, E, I, O, U bool CommonFunctions::isVowel(char letter) { return letter == 'a' || letter == 'e' || letter == 'i' || letter == 'o' || letter == 'u' || letter == 'A' || letter == 'E' || letter == 'I' || letter == 'O' || letter == 'U'; } // Simple Password Generator std::string CommonFunctions::password(int length) { srand(time(0)); static const std::string characters = "abcdefghijklmnopqrstuvwxyz" "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "0123456789" "!@#$%^&*"; std::string password = ""; for (int i = 1; i <= length; i++) password += characters[rand() % (characters.length() - 1)]; return password; } // ---------------------------------------------------------------------------------------------------- \\ /* .cpp(main) */ // #include // #include // #include "func.h" int main() { CommonFunctions CF; std::cout << CF.factorial(5) << std::endl; std::cout << std::endl; std::cout << CF.nk(3, 2) << std::endl; std::cout << std::endl; std::cout << CF.abN(3, 2, 4) << std::endl; std::cout << std::endl; std::cout << CF._abN(4, 2, 2) << std::endl; std::cout << std::endl; int arr[5] = { 1, 2, 3, 4, 5 }; std::cout << CF.sumArr(arr, 5) << std::endl; std::cout << std::endl; float arrF[5] = { 1.34, 1.452, 23.43, 232.343, 99.22 }; std::cout << CF.sumArr(arrF, 5) << std::endl; std::cout << std::endl; double arrD[5] = { 1.111111, 2.222222, 3.333333, 4.444444, 5.555555 }; std::cout << CF.sumArr(arrD, 5) << std::endl; std::cout << std::endl; std::cout << CF.sumFirst(100) << std::endl; std::cout << std::endl; std::cout << std::boolalpha << CF.isPrime(10) << std::endl; std::cout << std::endl; std::cout << std::boolalpha << CF.isPalindrome("abcba") << std::endl; std::cout << std::endl; std::cout << std::boolalpha << CF.isVowel('a') << std::endl; std::cout << std::endl; std::cout << CF.password(10) << std::endl; std::cout << std::endl; return 0; }