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倒序处理，线段树保存有多少空位

#include <iostream>
#include <cstdio>
using namespace std;
int n, ans[200005], uu[200005], vv[200005];
struct SGT{
	int sum[800005];
	void build(int o, int l, int r){
		if(l==r)	sum[o] = 1;
		else{
			int mid=(l+r)>>1;
			int lson=o<<1;
			int rson=lson|1;
			if(l<=mid)	build(lson, l, mid);
			if(mid<r)	build(rson, mid+1, r);
			sum[o] = sum[lson] + sum[rson];
		}
	}
	void update(int o, int l, int r, int x, int y){
		if(l==r){
			ans[l] = y;
			sum[o] = 0;
		}
		else{
			int mid=(l+r)>>1;
			int lson=o<<1;
			int rson=lson|1;
			if(sum[lson]>x)	update(lson, l, mid, x, y);
			else	update(rson, mid+1, r, x-sum[lson], y);
			sum[o] = sum[lson] + sum[rson];
		}
	}
}sgt;
int main(){
	while(scanf("%d", &n)!=EOF){
		sgt.build(1, 1, n);
		for(int i=1; i<=n; i++)
			scanf("%d %d", &uu[i], &vv[i]);
		for(int i=n; i; i--)
			sgt.update(1, 1, n, uu[i], vv[i]);
		for(int i=1; i<=n; i++)
			printf("%d ", ans[i]);
		printf("
");
	}
	return 0;
}