CCF/CSP-201812-3-CIDR合并
按照题意模拟，但是只有90，不想找bug了，毕竟算法不是自己想的，找起来也麻烦。
1 #include<bits/stdc++.h> 2 using namespace std; 3 #define inf 0x3f3f3f3f 4 #define LL long long 5 #define pui pair<unsigned int,int> 6 #define mp make_pair 7 #define x first 8 #define y second 9 10 const int maxn=1000005; 11 pui a[maxn]; 12 vector<pui>ans; 13 int n,q[4]={24,16,8,0},l[]={0,8,16,24,32}; 14 int base[]={(1<<24),(1<<16),(1<<8),1}; 15 ostream& operator << (ostream& out,pui& u){ 16 for(int i=0;i<4;++i){ 17 out<<u.x/base[i]%base[2]; 18 if(i<3)out<<"."; 19 }out<<"/"<<u.y; 20 return out; 21 } 22 bool issub(int i,int j){ 23 if(a[i].y==a[j].y){ 24 if(a[i].x==a[j].x){return 1;} 25 else{return 0;} 26 }else if(a[i].y>a[j].y)return 0; 27 else{ 28 if((a[j].x>>(32-a[i].y))==(a[i].x>>(32-a[i].y)))return 1; 29 else return 0; 30 } 31 } 32 bool ok(pui A,pui B){ 33 pui tmp;tmp.x=A.x;tmp.y=A.y-1; 34 if(A.y==B.y &&tmp.y>=0 && ((A.x>>(32-A.y)>>1)==(B.x>>(32-A.y)>>1)) 35 && (((A.x>>(32-A.y))&1)^((B.x>>(32-A.y))&1))==1 ) return 1; 36 return 0; 37 } 38 int main(){ 39 string str; 40 ios::sync_with_stdio(false); 41 cin>>n; 42 for(int i=0;i<n;++i){ 43 a[i].y=a[i].x=0; 44 cin>>str; 45 int pos=str.find('/'),cur=0,sz=str.size(); 46 unsigned tmp=0; 47 for(int ii=0;ii<sz&&str[ii]!='/';++ii){ 48 if(str[ii]=='.'){ 49 a[i].x+=(tmp<<q[cur++]); 50 tmp=0; 51 }else{ 52 tmp=tmp*10+(str[ii]-'0'); 53 } 54 } 55 if(tmp){ 56 a[i].x+=(tmp<<q[cur++]); 57 } 58 if(pos!=string::npos){ 59 for(int iii=pos+1;iii<sz;++iii) a[i].y=a[i].y*10+(str[iii]-'0'); 60 }else{ 61 a[i].y=l[cur]; 62 } 63 } 64 sort(a,a+n); 65 for(int i=0;i<n;++i){ 66 if(a[i].y==-1)continue; 67 int k=1; 68 while(i+k<=n && issub(i,i+k)) a[i+k].y=-1,k++; 69 i=i+k-1; 70 } 71 72 for(int i=0;i<n;++i){ 73 if(a[i].y==-1){continue;} 74 pui B=a[i]; 75 while(ans.size()&&ok(ans.back(),B)){ 76 B.x=ans.back().x;B.y=ans.back().y-1; 77 ans.pop_back(); 78 } 79 ans.push_back(B); 80 } 81 for(pui u:ans) cout<<u<<endl; 82 return 0; 83 }
