POJ 2828 Buy Tickets 线段树

node里储存剩余位置数

倒序更新

#include<stdio.h>#include<string.h>#include<algorithm>using namespace std;#define lson l,m,rt<<1#define rson m+1,r,rt<<1|1#define mid (r+l)>>1const int maxn=200300;int node[maxn<<2],a[maxn],b[maxn],ans[maxn];void build(int l,int r,int rt){node[rt]=r-l+1;if(r==l)return;int m=mid;build(lson);build(rson);}void update(int n,int l,int r,int rt){node[rt]--;if(l==r){ans[l]=b[n];return;}int m=mid;if(node[rt<<1]>=a[n])update(n,lson);else {a[n]-=node[rt<<1];update(n,rson);}}void init(){memset(a,0,sizeof(a));memset(node,0,sizeof(node));memset(b,0,sizeof(b));memset(ans,0,sizeof(ans));}int main(){int i,n;while(scanf("%d",&n)!=EOF){init();for(i=1;i<=n;i++){scanf("%d%d",&a[i],&b[i]);a[i]++;}build(1,n,1);for(i=n;i>=1;i--){update(i,1,n,1);}printf("%d",ans[1]);for(i=2;i<=n;i++){printf(" %d",ans[i]);}printf("\n");}return 0;}