codeforces -1214 E

题目https://codeforces.com/problemset/problem/1214/E

就是得知奇数之间不产生影响，先造出一条链，再用偶数往里插就行。链要di从大到小排个序呀！！

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<vector>
#define maxn 202000
using namespace std;
struct Node {
	int ans;
	int pos;
}list[maxn];
bool bml(Node a, Node b) {
	return a.ans > b.ans;
}
vector<int>ans;
int main() {
	int n;

	scanf("%d", &n);
	for (int i = 1; i <= n; i++) {
		scanf("%d", &list[i].ans);
		list[i].pos = i * 2 - 1;//奇数
	}
	sort(list + 1, list + 1 + n, bml);
	for (int i = 1; i < n; i++) {
		printf("%d %d\n", list[i].pos, list[i + 1].pos);
		ans.push_back(list[i].pos);
	}
	ans.push_back(list[n].pos);
	
	for (int i = 1; i <= n; i++) {
		int t = list[i].ans + i - 2;
		
		printf("%d %d\n", ans[t], list[i].pos + 1);
		if (ans.size()-1 == t) ans.push_back(list[i].pos + 1);
	}
	return 0;
}