20多天没写题啊。。。连键盘长什么样都忘了额。。。
用这道并查集水题练手2333
1 /************************************************************** 2 Problem: 1370 3 User: rausen 4 Language: C++ 5 Result: Accepted 6 Time:36 ms 7 Memory:816 kb 8 ****************************************************************/ 9 10 #include <cstdio> 11 #include <algorithm> 12 13 using namespace std; 14 const int N = 1005; 15 16 int n, m, ans; 17 int fa[N << 1], a[N]; 18 19 int read() { 20 int x = 0; 21 char ch = getchar(); 22 while (ch < '0' || '9' < ch) 23 ch = getchar(); 24 while ('0' <= ch && ch <= '9') 25 (x *= 10) += ch - '0', ch = getchar(); 26 return x; 27 } 28 29 int find_fa(int x) { 30 return x == fa[x] ? x : fa[x] = find_fa(fa[x]); 31 } 32 33 int main() { 34 int i, x, y; 35 char st[5]; 36 n = read(), m = read(); 37 for (i = 1; i <= n * 2; ++i) fa[i] = i; 38 for (i = 1; i <= m; ++i) { 39 scanf("%s", st); 40 x = read(), y = read(); 41 if (st[0] == 'F') 42 fa[find_fa(x)] = find_fa(y); 43 else fa[find_fa(x)] = find_fa(y + n), fa[find_fa(y)] = find_fa(x + n); 44 } 45 for (i = 1; i <= n; ++i) 46 a[i] = find_fa(i); 47 sort(a + 1, a + n + 1); 48 for (i = 1; i <= n; ++i) 49 if (a[i] == 1 || a[i] != a[i - 1]) 50 ++ans; 51 printf("%d ", ans); 52 return 0; 53 }