标签:
[2016-01-27][UVA][1395][D - Slim Span]1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 | #include <vector> #include <list> #include <map> #include <set> #include <deque> #include <queue> #include <stack> #include <bitset> #include <algorithm> #include <functional> #include <numeric> #include <utility> #include <sstream> #include <iostream> #include <iomanip> #include <cstdio> #include <cmath> #include <cstdlib> #include <cctype> #include <string> #include <cstring> #include <cstdio> #include <cmath> #include <cstdlib> #include <ctime> using namespace std; const int maxn = 110; int n,m; struct Edge{ int u,v; long long c; bool operator < ( const Edge & a) const { return c < a.c; } }e[maxn*maxn/2]; int fa[maxn]; void ini(){ for ( int i = 0;i < n + 5;i++) fa[i] = i; } int fnd( int x){ return x == fa[x] ? x : (fa[x] = fnd(fa[x])); } vector<Edge> chs; long long kruskal() { sort(e,e + m); long long k = -1; for ( int j = 0;j < m;j++) { int ct = 0; long long res = 0; ini(); chs.clear(); for ( int i = j;i < m;i++) { if (ct == n - 1) break ; int u = e[i].u,v = e[i].v; u = fnd(u); v = fnd(v); if (u != v) { fa[u] = v; res += e[i].c; chs.push_back(e[i]); ct++; } } if (ct == n-1 && (k > chs[chs.size() - 1].c - chs[0].c || k == -1)) k = chs[chs.size() - 1].c - chs[0].c; } return k; } int main() { //freopen("out.txt","w",stdout); while (~ scanf ( "%d%d" ,&n,&m) && (m || n)) { int a,b,c; for ( int i = 0;i < m;i++) { scanf ( "%d%d%d" ,&a,&b,&c); e[i].u =a; e[i].v =b; e[i].c =c; } printf ( "%lld\n" ,kruskal()); } return 0; } |
[2016-01-27][UVA][1395][D -?Slim Span]
标签:
原文地址:http://www.cnblogs.com/qhy285571052/p/5164901.html