HDU 4022 Bombing STL/二分

用stl的set和map

#include<cstdio> #include<cstring> #include<string> #include<iostream> #include<algorithm> #include<map> #include<set> #include<iterator> using namespace std; typedef map<int,multiset<int> > def; void pop(def &a,def &b,int k) { printf("%d\n",a[k].size()); for(multiset<int>::iterator i=a[k].begin();i!=a[k].end();i++) b[*i].erase(k); a[k].clear(); } int main() { int n,m,x,y; while(1) { scanf("%d%d",&n,&m); if(n==0&&m==0)return 0; def h;def l; for(int i=0;i<n;i++) { scanf("%d%d",&x,&y); h[x].insert(y); l[y].insert(x); } for(int j=0;j<m;j++) { scanf("%d%d",&x,&y); if(x==0) pop(h,l,y); else pop(l,h,y); } printf("\n"); } return 0; }

或者二分

#include<cstdio> #include<cstring> #include<algorithm> using namespace std; const int N=100010; struct Node { int x,y; }p[N]; bool hv[N]; int a[N],b[N]; bool cmp1(int k1,int k2) { return p[k1].x < p[k2].x; } bool cmp2(int k1,int k2) { return p[k1].y < p[k2].y; } int main() { int n,m; while(scanf("%d%d",&n,&m) && !(n==0 && m==0)) { memset(hv,true,sizeof(hv)); for(int i=1;i<=n;i++) { scanf("%d%d",&p[i].x,&p[i].y); a[i]=b[i]=i; } sort(a+1,a+1+n,cmp1); sort(b+1,b+1+n,cmp2); while(m--) { int c,d; scanf("%d%d",&c,&d); int ans=0; if(c==0) { int l=1,r=n,t; while(l<r) { int mid=(l+r)/2; if(p[a[mid]].x >= d) r=mid; else l=mid+1; } t=l; while(t<=n && p[a[t]].x == d) ans+=hv[a[t]],hv[a[t]]=false,t++; } else { int l=1,r=n,t; while(l<r) { int mid=(l+r)/2; if(p[b[mid]].y >= d) r=mid; else l=mid+1; } t=l; while(t<=n && p[b[t]].y == d) ans+=hv[b[t]],hv[b[t]]=false,t++; } printf("%d\n",ans); } puts(""); } }