「BZOJ」「3262」陌上花开

CDQ分治

　　WA ：在solve时，对y、z排序以后，没有处理「y、z相同」的情况，也就是说可能（1，2，3）这个点被放到了（2，2，3）的后面，也就是统计答案在前，插入该点在后……也就没有统计到！

　　sad

 #include<cstdio>
 #include<cstring>
 #include<cstdlib>
 #include<iostream>
 #include<algorithm>
 using namespace std;

 const int N = ;
 int n,k;
 struct node{
     int x,y,z,id;
 }a[], b[];
 bool operator != (node a,node b){
     return a.x != b.x || a.y != b.y || a.z != b.z;
 }
 bool operator < (node a,node b){
     return a.x < b.x || (a.x == b.x && a.y < b.y) || (a.x == b.x && a.y == b.y && a.z < b.z);
 }
 bool cmp(node a,node b){
     return a.y < b.y || (a.y == b.y && a.z < b.z) || (a.y == b.y && a.z == b.z && a.id < b.id);
 }
 int ans[N], rank[N], num[N];

 int val[N], vis[N], times;
 inline int lowbit(int x){
     return x & (-x);
 }
 void add(int pos, int v){
     for(int i = pos; i <= k; i += lowbit(i))
         if (vis[i] == times) val[i] += v;
         else val[i] = v, vis[i] = times;
 }
 int query(int pos){
     int ans = ;
     for(int i = pos; i; i -= lowbit(i))
         if (vis[i] == times)
             ans += val[i];
     return ans;
 }

 void solve(int l,int r){
     int mid = l + r >> ;
     if (l < mid) solve(l, mid);
     sort(a + l, a + r + , cmp);
     times ++;
     for(int i = l; i <= r; i ++)
         if (a[i].id <= mid) add(a[i].z, num[a[i].id]);
         else rank[a[i].id] += query(a[i].z);
     sort(a + l, a + r + );
     if (mid +  < r) solve(mid + , r);
 }
 int main(){
     freopen("3262.in", "r", stdin);
     freopen("3262.out", "w", stdout);
     scanf("%d%d",&n,&k);
     for(int i = ; i <= n; i ++)
         scanf("%d%d%d",&a[i].x, &a[i].y, &a[i].z);
     sort(a + , a + n + );
     for(int i = ; i <= n; i ++) b[i] = a[i];
     int cnt = ;
     for(int i = ; i <= n; i ++)
         if (b[i] != b[i - ]) a[++ cnt] = b[i], num[cnt] = ;
         else num[cnt] ++;
     for(int i = ; i <= cnt; i ++) a[i].id = i, rank[i] = num[i] - ;
 //    for(int i = 1; i <= cnt; i ++) printf("%d %d %d num = %d\n",a[i].x, a[i].y, a[i].z, num[i]);
     solve(, cnt);
 //    for(int i = 1; i <= cnt; i ++) printf("rank[%d] = %d\n",i,rank[i]);
     for(int i = ; i <= cnt; i ++)
         ans[rank[i]] += num[i];
     for(int i = ; i < n; i ++) printf("%d\n",ans[i]);
     return ;
 }