GFG RANDOM NUMBER FROM STREAM

#include <bits/stdc++.h>
#include <time.h>

using namespace std;

int selectRandom(int x) {
    static int res; 
    static int count = 0; 
    count++; 
    if (count == 1) res = x;
    else {
        int i = rand() % count;
        if (i == count - 1)
            res = x;
    }
    return res;
}
 
int main() {
    int stream[] = {1, 2, 3, 4};
    int n = sizeof(stream) / sizeof(stream[0]);

    srand(time(NULL));
    for (int i = 0; i < n; ++i)
        cout << "Random number from first " << i + 1 << " numbers is " << selectRandom(stream[i]) << endl;
    return 0;
}