Forth

#include <iostream>
using namespace std;

int main() {
	int x, i;
	cin >> x;

	if (x == 1) { cout << "2\nDUP DROP\n"; return 0; }

	cout << __lg(x) * 5 << endl;

	for (i = 0; i < __lg(x); ++i) {
		cout << "DUP" << " ";
		cout << "DUP" << " ";
		cout << "+" << " ";
	}

	while (--i >= 0) {
		cout << "SWAP" << " ";
		cout << (((x >> i) & 1) ? "+" : "DROP") << " ";
	}

	cout << endl;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED