http://ybt.ssoier.cn:8088/problem_show.php?pid=1388
方法一：普通模拟，结构体写法
1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 using namespace std; 5 struct node 6 { 7 string name; 8 int father; 9 }; 10 node a[50009]; 11 int findx(int i) 12 { 13 if(a[i].father!=i)a[i].father=findx(a[i].father); 14 return a[i].father; 15 } 16 void unionn(int r,int t) 17 { 18 int q=findx(t); 19 if(r!=q)a[q].father=r; 20 } 21 int main() 22 { 23 char c; 24 int tot=0; 25 int father; 26 string s; 27 do 28 { 29 cin>>c; 30 if(c=='$')break; 31 cin>>s; 32 int r=-1; 33 for(int i=1;i<=tot;i++) 34 if(a[i].name==s) 35 { 36 r=i; 37 break;\找到就可以跳出； 38 } 39 if(r==-1) 40 { 41 r=++tot; 42 a[r].father=r; 43 a[r].name=s; 44 } 45 if(c=='#') 46 { 47 father=a[r].father; 48 continue; 49 } 50 if(c=='+') 51 { 52 unionn(father,r); 53 continue; 54 } 55 if(c=='?') 56 cout<<s<<" "<<a[findx(r)].name<<endl; 57 }while(1); 58 return 0; 59 }
方法二：使用STL MAP
1 #include<iostream> 2 #include<cstdio> 3 #include<algorithm> 4 #include<string> 5 #include<map> 6 7 using namespace std; 8 map<string, string>p; 9 string findth(string x) 10 { 11 if (p[x] == x) return x; 12 return p[x] = findth(p[x]); 13 } 14 15 void unionn(string x, string y) 16 { 17 string xx = findth(x); 18 //string yy = findth(y); 19 if (xx != y) p[y] = xx; 20 } 21 int main() 22 { 23 string s; 24 string t; 25 string t1; 26 string t2; 27 while (cin >> s, s != "$") { 28 if (s[0] == '#') { 29 t = s.substr(1); 30 if (p[t] == "") p[t] = t; 31 } 32 else if (s[0] == '+') { 33 t1 = s.substr(1); 34 unionn(t, t1); 35 } 36 else if (s[0] == '?') { 37 t2 = s.substr(1); 38 findth(t2);//找到祖先 39 cout << t2 << " " << p[t2] << endl; 40 } 41 } 42 return 0; 43 }