Recursion in C++ is a programming technique where a function calls itself repeatedly to solve a problem. It is commonly used for tasks that can be divided into smaller subproblems.<\/p>\n\n\n\n
Recursion is a process in which a function calls itself until a specific condition is met.<\/p>\n\n\n\n
A recursive function has two important parts:<\/p>\n\n\n\n
Recursion is useful because it:<\/p>\n\n\n\n
return_type function_name(parameters) {
if (base_condition) {
return value;
}
return function_name(smaller_problem);
}<\/code><\/pre>\n\n\n\nExample of Recursion<\/h2>\n\n\n\n#include <iostream>
using namespace std;
void countDown(int n) {
if (n == 0) {
return;
}
cout << n << endl;
countDown(n - 1);
}
int main() {
countDown(5);
return 0;
}<\/code><\/pre>\n\n\n\nOutput<\/h2>\n\n\n\n5
4
3
2
1<\/code><\/pre>\n\n\n\nHow Recursion Works<\/h2>\n\n\n\n\n- Function is called<\/li>\n\n\n\n
- Function performs a task<\/li>\n\n\n\n
- Function calls itself with smaller input<\/li>\n\n\n\n
- Process repeats<\/li>\n\n\n\n
- Base case stops recursion<\/li>\n<\/ol>\n\n\n\n
Example: Factorial Using Recursion<\/h2>\n\n\n\n
Factorial formula:<\/p>\n\n\n\n