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

const int N = 110;
int a[N];
int st[10];
struct Node {
    int st, ed;
};
vector<Node> q;
/*
5
1 2 3 3 2
*/
int main() {
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i]; // 密码数组

    for (int i = 1; i <= n; i++) {
        if (!st[a[i]]) {
            st[a[i]] = 1;
            for (int j = n; j; j--)
                if (a[i] == a[j]) {
                    q.push_back({i, j});
                    break;
                }
        }
    }
    // 从左到右枚举，所以，不再需再进行按左端点排序,现在就是按左端点排序完的

    for (int i = 0; i < q.size(); i++) cout << q[i].st << " " << q[i].ed << endl;

    return 0;
}