【CF】244C Checkposts

题目需要求啥很明确了。主要思想是先计算机联通块，然后每个块内找到一个最小值（以及该值的次数）。最小值和结果1，次数乘积为结果2。联通块tarjan可解。

 /* 427C */
 #include <iostream>
 #include <string>
 #include <map>
 #include <queue>
 #include <set>
 #include <stack>
 #include <vector>
 #include <deque>
 #include <algorithm>
 #include <cstdio>
 #include <cmath>
 #include <ctime>
 #include <cstring>
 #include <climits>
 #include <cctype>
 #include <cassert>
 #include <functional>
 using namespace std;
 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define mpii            map<int,int>
 #define vi                vector<int>
 #define pii                pair<int,int>
 #define vpii            vector<pair<int,int> >
 #define rep(i, a, n)     for (int i=a;i<n;++i)
 #define per(i, a, n)     for (int i=n-1;i>=a;--i)
 #define pb                 push_back
 #define mp                 make_pair
 #define fir                first
 #define sec                second
 #define all(x)             (x).begin(),(x).end()
 #define SZ(x)             ((int)(x).size())
 #define lson            l, mid, rt<<1
 #define rson            mid+1, r, rt<<1|1

 const int maxn = 1e5+;
 const int mod = 1e9+;
 vi vc[maxn];
 int low[maxn], bn[maxn], pre[maxn];
 int S[maxn], top;
 int dfs_clock, block;
 int n, m;
 int C[maxn];
 int mn[maxn], cnt[maxn];

 void init() {
     memset(pre, , sizeof(pre));
     memset(bn, , sizeof(bn));
     memset(mn, 0x3f, sizeof(mn));
     memset(cnt, , sizeof(cnt));
     dfs_clock = block = top = ;
 }

 void tarjan(int u) {
     int v;

     S[top++] = u;
     pre[u] = low[u] = ++dfs_clock;
     rep(i, , SZ(vc[u])) {
         v = vc[u][i];
         if (!pre[v]) {
             tarjan(v);
             low[u] = min(low[u], low[v]);
         } else if (!bn[v]) {
             low[u] = min(low[u], pre[v]);
         }
     }

     if (low[u] == pre[u]) {
         ++block;
         do {
             bn[S[--top]] = block;
         } while (S[top]!=u);
     }
 }

 void solve() {
     rep(i, , n+)
         if (!pre[i])
             tarjan(i);
     int b, c;

     rep(i, , n+) {
         b = bn[i];
         c = C[i];
         if (c< mn[b]) {
             mn[b] = c;
             cnt[b] = ;
         } else if (c == mn[b]) {
             ++cnt[b];
         }
     }

     __int64 ans = , cost = ;
     rep(i, , block+) {
         cost += mn[i];
         ans = (ans * cnt[i])%mod;
     }

     printf("%I64d %I64d\n", cost, ans);
 }

 int main() {
     ios::sync_with_stdio(false);
     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
         freopen("data.out", "w", stdout);
     #endif

     int u, v;

     scanf("%d", &n);
     rep(i, , n+)
         scanf("%d", &C[i]);;
     scanf("%d", &m);
     while (m--) {
         scanf("%d %d", &u, &v);
         vc[u].pb(v);
     }

     init();
     solve();

     #ifndef ONLINE_JUDGE
         printf("time = %d.\n", (int)clock());
     #endif

     return ;
 }