http://acm.hdu.edu.cn/showproblem.php?pid=1541 结点更新求最左区间的个数

/* * 少写一个询问的函数，以为一个更新的函数就够了，结果。。。。 * 就是结点更新求最左区间的个数 */#include <iostream>#include <cstdio>#include <cstring>#define LL(x) ((x) << 1)#define RR(x) ((x) << 1 | 1)using namespace std;const int N = 32005;struct Seg_tree{int l, r;int sum;int mid(){return (l + r) >> 1;}}tree[3 * N];int pos[N];inline void Build(int l, int r, int node){tree[node].l = l;tree[node].r = r;tree[node].sum = 0;if(l == r)return ;int mid = (l + r) >> 1;Build(l, mid, LL(node));Build(mid + 1, r, RR(node));}inline void Update(int node, int dx){if(tree[node].l == tree[node].r && tree[node].l == dx){//pos[tree[node].sum]++;tree[node].sum += 1;//printf("dx :: %d tree[node].sum :: %d/n", dx, tree[node].sum);return ;}/*if(tree[node].sum){tree[LL(node)].sum = tree[RR(node)].sum = tree[node].sum;}*/int mid = tree[node].mid();if(dx <= mid)Update(LL(node), dx);elseUpdate(RR(node), dx);tree[node].sum += 1;}inline int Query(int l, int r, int node){if(l <= tree[node].l && tree[node].r <= r){return tree[node].sum;}int mid = tree[node].mid();if(r <= mid){return Query(l , r, LL(node));} else if(l > mid){return Query(l, r, RR(node));} else{return Query(l, mid, LL(node))+ Query(mid + 1, r, RR(node));}}int main(){int n;while(scanf("%d", &n) != EOF){int x, y;Build(0, 32000, 1);//memset(pos, 0, sizeof(pos));for(int i = 0 ;i < n; i++)pos[i] = 0;int temp = n;while(temp--){scanf("%d %d", &x, &y);pos[Query(0, x, 1)]++;Update(1, x);}//puts("===");for(int i = 0; i < n; i++)printf("%d/n", pos[i]);}}