POJ 2828 Buy Tickets 线段树

#include <stdio.h>
#include <string.h>

const int MAXN = 200010;

int pos[MAXN], val[MAXN], ans[MAXN];

struct Tree_Node
{
int left, right;
int num;
} tree[MAXN<<2];

void build(int left, int right, int step)
{
tree[step].left = left;
tree[step].right = right;
tree[step].num = right - left + 1;
if(left == right)
{
return;
}
int mid = (left + right) >> 1;
build(left, mid, step<<1);
build(mid+1, right, step<<1|1);
}

void insert(int posi, int vali, int step)
{
tree[step].num--;
if(tree[step].left == tree[step].right)
{
ans[tree[step].left] = vali;
return;
}
if(posi < tree[step<<1].num)
insert(posi, vali, step<<1);
else
insert(posi - tree[step<<1].num, vali, step<<1|1);
}

int main()
{
int n;
while(scanf("%d", &n) != EOF)
{
build(0, n-1, 1);
for(int i = 0; i < n; i++)
scanf("%d %d", &pos[i], &val[i]);
for(int i = n-1; i >= 0; i--)
insert(pos[i], val[i], 1);
for(int i = 0; i < n-1; i++)
printf("%d ", ans[i]);
printf("%d\n", ans[n-1]);
}
return 0;
}