题目链接:点击打开链接
思路:
带权并查集水题。 带权并查集可以知道在一个集合里的两点间距离。那么这种同义反义关心恰好对应距离的奇偶。
附上一图:
这就是合并的过程。
细节参见代码:
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
#include <stack>
#include <ctime>
#include <bitset>
#include <cstdlib>
#include <cmath>
#include <set>
#include <list>
#include <deque>
#include <map>
#include <queue>
#define Max(a,b) ((a)>(b)?(a):(b))
#define Min(a,b) ((a)<(b)?(a):(b))
using namespace std;
typedef long long ll;
typedef long double ld;
const double eps = 1e-6;
const double PI = acos(-1);
const int mod = 1000000000 + 7;
const int INF = 0x3f3f3f3f;
// & 0x7FFFFFFF
const int seed = 131;
const ll INF64 = ll(1e18);
const int maxn = 1e5+10;
int T,n,m,q,p[maxn],dist[maxn];
map<string, int> mp;
char s[33], s1[33];
int _find(int x) {
if(p[x] == x) return x;
int oldfa = p[x];
p[x] = _find(p[x]);
dist[x] = (dist[x] + dist[oldfa])%2;
return p[x];
}
void init() {
for(int i = 1; i <= n; i++) {
p[i] = i;
dist[i] = 0;
}
}
int main() {
scanf("%d%d%d", &n, &m, &q);
for(int i = 1; i <= n; i++) {
scanf("%s", s);
mp[s] = i;
}
init();
for(int i = 1; i <= m; i++) {
int id; scanf("%d%s%s", &id, s, s1);
int id1 = mp[s], id2 = mp[s1];
int x = _find(id1), y = _find(id2);
if(x != y) {
printf("YES\n");
if(id == 1) p[x] = y, dist[x] = (dist[id2]-dist[id1]+2)%2;
else p[x] = y, dist[x] = (dist[id2]-dist[id1]+1+2)%2;
}
else {
int cur = (dist[id1]-dist[id2]+2)%2;
if(id == 1) {
if(cur & 1) printf("NO\n");
else printf("YES\n");
}
else {
if(cur & 1) printf("YES\n");
else printf("NO\n");
}
}
}
while(q--) {
scanf("%s%s", s, s1);
int id1 = mp[s], id2 = mp[s1];
int x = _find(id1), y = _find(id2);
if(x != y) printf("3\n");
else {
int cur = (dist[id1] - dist[id2] + 2)%2;
if(cur & 1) printf("2\n");
else printf("1\n");
}
}
return 0;
}