ALDS1_2_D シェルソートをC++で解いてみた[AIZU ONLINE JUDGE]

#include <bits/stdc++.h>
using namespace std;

void print(int a[], int n, int *cnt, vector<int> g) {
    cout << g.size() << endl;
    for(int i = g.size() - 1; i >= 0; i--) {
        cout << g[i] << (i == 0 ? '\n' : ' ');
    }
    cout << *cnt << endl;
    for(int i = 0; i < n; i++) {
        cout << a[i] << endl;
    }
}

void insertion_sort(int a[], int n, int h, int *cnt) {
    for(int i = h; i < n; i++) {
        int v = a[i];
        int j = i - h;
        while(j >= 0 && a[j] > v) {
            a[j + h] = a[j];
            j -= h;
            ++*cnt;
        }
        a[j + h] = v;
    }
}

void shell_sort(int a[], int n, int *cnt, vector<int> g) {
    *cnt = 0;
    int x = 1;
    while(x <= n) {
        g.push_back(x);
        x = 3 * x + 1;
    }
    int m = g.size();
    for(int i = m - 1; i >= 0; i--) {
        insertion_sort(a, n, g[i], cnt);
    }
}

int main() {
    int n;
    cin >> n;
    int a[n];
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }
    int cnt = 0;
    vector<int> g;
    // print(a, n, &cnt);
    // insertion_sort(a, n, 1, &cnt);
    shell_sort(a, n, &cnt, g);
    print(a, n, &cnt, g);
    return 0;
}