What will be the output of the following C code?
#include <stdio.h>
int run(int n) {
if (n <= 0) return 0;
return n + run(n - 2);
}
int main(void) {
printf("%d", run(7));
return 0;
}run(7) = 7 + run(5) = 7 + 5 + run(3) = 7 + 5 + 3 + run(1) = 7 + 5 + 3 + 1 + run(-1) = 16.
How many times is the function fib() executed in total when computing fib(4)?
int fib(int n) {
if (n <= 1) return n;
return fib(n - 1) + fib(n - 2);
}Calls: fib(4) [1], fib(3) [2], fib(2) [3], fib(1) [4], fib(0) [5], fib(1) [6], fib(2) [7], fib(1) [8], fib(0) [9]. Total = 9 calls.
What will be the output of the following C code?
#include <stdio.h>
void g(int n) {
if (n > 0) {
g(n - 1);
printf("%d", n);
}
}
int main(void) {
g(3);
return 0;
}Unwinding prints 1, then 2, then 3 -> 123.
Which recursive structure is used in quicksort partition step?
Quicksort divides the array into sub-arrays around a pivot and recursively sorts them.
What does the following recursive function compute?
int count(int arr[], int n) {
if (n <= 0) return 0;
return (arr[n-1] % 2 != 0) + count(arr, n-1);
}arr[n-1] % 2 != 0 returns 1 if element is odd, summing up count of odd elements.