题解

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<vi> vii;
typedef unsigned us;
#define INF 1e9
#define nl endl
#define faster ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define rep(i, a, b) for (int i = int(a); i < int(b); i++)
#define REP(i, a, b) for (int i = int(a); i <= int(b); i++)
#define drep(i, a, b) for (int i = int(a); i > int(b); i--)
#define DREP(i, a, b) for (int i = int(a); i >= int(b); i--)
const int c3 = 1e3 + 2, c4 = 1e4 + 2, c5 = 1e5 + 2, c6 = 1e6 + 2;
int main() {
    faster;
	int n, *f;
	cin >> n;
	f = new int[n + 10];
	REP (i, 1, n) {
		int p;
		cin >> p;
		f[p] = i;
	}
	int head = 0;
	REP (i, 1, n) {
		if (f[i] < head) cout << "," << i;
		else {
			head = f[i];
			if (i != 1) cout << endl;
			cout << i;
		}
	}

	delete[] f;
	return 0;
}