HDU 5618:Jam's problem again(CDQ分治+树状数组处理三维偏序)

http://acm.hdu.edu.cn/showproblem.php?pid=5618

题意:……

思路:和NEUOJ那题一样的。重新写了遍理解了一下,算作处理三维偏序的模板了。

 #include <cstdio>
#include <algorithm>
#include <iostream>
#include <cstring>
using namespace std;
#define INF 0x3f3f3f3f
#define N 100010
typedef long long LL;
struct node {
int x, y, z, id, f;
} p[N], s[N];
int ans[N], same[N], bit[N], gap; bool cmpx(const node &a, const node &b) { if(a.x != b.x) return a.x < b.x; if(a.y != b.y) return a.y < b.y; return a.z < b.z; }
bool cmpy(const node &a, const node &b) { if(a.y != b.y) return a.y < b.y; if(a.x != b.x) return a.x < b.x; return a.z < b.z; }
bool cmpid(const node &a, const node &b) { return a.id < b.id; }
bool check(node a, node b) { return a.x == b.x && a.y == b.y && a.z == b.z; } int lowbit(int x) { return x & (-x); } void update(int x, int w) { while(x <= gap) bit[x] += w, x += lowbit(x); } int query(int x) { int ans = ; while(x) ans += bit[x], x -= lowbit(x); return ans; } void CDQ(int l, int r) {
if(l == r) return ;
int m = (l + r) >> ;
CDQ(l, m); CDQ(m + , r);
int cnt = ;
// 标记是在左边还是右边
for(int i = l; i <= r; i++) s[++cnt] = p[i], s[cnt].f = i <= m ? : ;
sort(s + , s + + cnt, cmpy);
for(int i = ; i <= cnt; i++)
if(!s[i].f) update(s[i].z, );
else ans[s[i].id] += query(s[i].z);
for(int i = ; i <= cnt; i++)
if(!s[i].f) update(s[i].z, -);
} int main() {
int t, n;
scanf("%d", &t);
while(t--) {
scanf("%d", &n); gap = ;
for(int i = ; i <= n; i++) {
scanf("%d%d%d", &p[i].x, &p[i].y, &p[i].z);
p[i].id = i; if(p[i].z > gap) gap = p[i].z;
}
sort(p + , p + + n, cmpx);
// 离散化
for(int i = ; i <= n; ) {
int j = i + ;
while(j <= n && check(p[j], p[i])) j++;
while(i < j) same[p[i++].id] = p[j-].id;
}
for(int i = ; i <= n; i++) p[i].x = i;
memset(bit, , sizeof(bit));
memset(ans, , sizeof(ans));
CDQ(, n);
sort(p + , p + + n, cmpid);
for(int i = ; i <= n; i++) printf("%d\n", ans[same[i]]);
}
return ;
}
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