[HDOJ5876]Sparse Graph（补图最短路）

  1 #include <algorithm>
  2 #include <iostream>
  3 #include <iomanip>
  4 #include <cstring>
  5 #include <climits>
  6 #include <complex>
  7 #include <fstream>
  8 #include <cassert>
  9 #include <cstdio>
 10 #include <bitset>
 11 #include <vector>
 12 #include <deque>
 13 #include <queue>
 14 #include <stack>
 15 #include <ctime>
 16 #include <set>
 17 #include <map>
 18 #include <cmath>
 19 using namespace std;
 20 #define fr first
 21 #define sc second
 22 #define cl clear
 23 #define BUG puts("here!!!")
 24 #define W(a) while(a--)
 25 #define pb(a) push_back(a)
 26 #define Rint(a) scanf("%d", &a)
 27 #define Rll(a) scanf("%I64d", &a)
 28 #define Rs(a) scanf("%s", a)
 29 #define Cin(a) cin >> a
 30 #define FRead() freopen("in", "r", stdin)
 31 #define FWrite() freopen("out", "w", stdout)
 32 #define Rep(i, len) for(int i = 0; i < (len); i++)
 33 #define For(i, a, len) for(int i = (a); i < (len); i++)
 34 #define Cls(a) memset((a), 0, sizeof(a))
 35 #define Clr(a, x) memset((a), (x), sizeof(a))
 36 #define Full(a) memset((a), 0x7f7f7f, sizeof(a))
 37 #define lrt rt << 1
 38 #define rrt rt << 1 | 1
 39 #define pi 3.14159265359
 40 #define RT return
 41 #define lowbit(x) x & (-x)
 42 #define onecnt(x) __builtin_popcount(x)
 43 typedef long long LL;
 44 typedef long double LD;
 45 typedef unsigned long long ULL;
 46 typedef pair<int, int> pii;
 47 typedef pair<string, int> psi;
 48 typedef pair<LL, LL> pll;
 49 typedef map<string, int> msi;
 50 typedef vector<int> vi;
 51 typedef vector<LL> vl;
 52 typedef vector<vl> vvl;
 53 typedef vector<bool> vb;
 54 
 55 const int maxn = 200200;
 56 const int inf = 10000010;
 57 set<int> G[maxn];
 58 set<int> x;
 59 int n, m, s;
 60 int d[maxn];
 61 
 62 void bfs(int s) {
 63     Clr(d, -1);
 64     d[s] = 0;
 65     queue<int> q;
 66     q.push(s); x.erase(s);
 67     set<int>::iterator v;
 68     while(!q.empty()) {
 69         int u = q.front(); q.pop();
 70         set<int> y;
 71         for(v = x.begin(); v != x.end(); v++) {
 72             if(G[u].find(*v) == G[u].end()) {
 73                 if(d[*v] == -1) d[*v] = d[u] + 1;
 74                 else d[*v] = min(d[*v], d[u] + 1);
 75                 y.insert(*v);
 76                 q.push(*v);
 77             }
 78         }
 79         for(v = y.begin(); v != y.end(); v++)    {
 80             x.erase(*v);
 81         }
 82     }
 83 }
 84 
 85 int main() {
 86     // FRead();
 87     int T, u, v;
 88     Rint(T);
 89     W(T) {
 90         Rint(n); Rint(m);
 91         x.clear();
 92         For(i, 1, n+1) {
 93             x.insert(i);
 94             G[i].clear();
 95         }
 96         Rep(i, m) {
 97             Rint(u); Rint(v);
 98             G[u].insert(v); G[v].insert(u);
 99         }
100         Rint(s);
101         bfs(s);
102         For(i, 1, n+1) {
103             if(i == s) continue;
104             printf("%d%c", d[i], i == n ? ‘\n‘ : ‘ ‘);
105         }
106     }
107     RT 0;
108 }