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#include <iostream>
#include <climits>
#include <vector>
#include <algorithm>
//#include <gtest/gtest.h>
using std::vector;
vector<int> optimal_sequence(int n) {
vector<int> sequence;
int stepsCount[n];
// the path int array indicates the next step to reduce it:
// 1: minus 1
// 2: divide by 2
// 3: divide by 3
int path[n];
int div2Steps, div3Steps, minus1Steps;
for (int i = 1; i < n; i++) {
int j = i + 1;
div2Steps = INT_MAX;
div3Steps = INT_MAX;
if (j % 3 == 0) {
div3Steps = stepsCount[j / 3 - 1];
}
if (j % 2 == 0) {
div2Steps = stepsCount[j / 2 - 1];
}
minus1Steps = stepsCount[i - 1];
int minStepsCount = std::min(minus1Steps,
std::min(div2Steps, div3Steps));
stepsCount[i] = minStepsCount + 1;
if (minStepsCount == minus1Steps) {
path[i] = 1;
continue;
}
if (minStepsCount == div2Steps) {
path[i] = 2;
continue;
}
if (minStepsCount == div3Steps) {
path[i] = 3;
}
}
sequence.push_back(n);
while (n > 1) {
int i = path[n - 1];
if (i == 3) {
n = n / 3;
sequence.push_back(n);
continue;
}
if (i == 2) {
n = n / 2;
sequence.push_back(n);
continue;
}
n = n - 1;
sequence.push_back(n);
}
reverse(sequence.begin(), sequence.end());
return sequence;
}
//TEST(PrimitiveCalc, Calc1) {
// ASSERT_EQ(2, optimal_sequence(6).size() - 1);
//}
//
//TEST(PrimitiveCalc, Calc2) {
// ASSERT_EQ(14, optimal_sequence(96234).size() - 1);
//}
int main() {
int n;
std::cin >> n;
vector<int> sequence = optimal_sequence(n);
std::cout << sequence.size() - 1 << std::endl;
for (size_t i = 0; i < sequence.size(); ++i) {
std::cout << sequence[i] << " ";
}
}
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