Poj 1861 Kruskal

# Include <iostream> # include <algorithm> # include <cstring> # include <queue> # include <cstdio> # include <map> using namespace STD; const int maxn = 1001; const int maxm = 15001; struct edge {int U, V, W;} edges [maxm]; int CMP (const void * a, const void * B) // sort by length {edge AA = * (const edge *) A; edge BB = * (const edge *) B; return AA. w-BB. w;} int parent [maxn]; int rank [maxn]; int n, m; int ans [maxn], AI; int num, maxedge; void Make_set () {for (INT I = 1; I <= N; I ++) {parent [I] = I; rank [I] = 1 ;}} int find (int x) {While (X! = Parent [x]) x = parent [X]; return X;} void Union (int x, int y) {x = find (X ); y = find (y); If (x = y) return; If (rank [x]> rank [y]) {parent [y] = X; rank [x] + = rank [y];} else {parent [x] = y; rank [y] + = rank [x] ;}} void Kruskal () {ai = 0; num = 0; int U, V; make_set (); For (INT I = 1; I <= m; I ++) {u = edges [I]. u; V = edges [I]. v; If (find (u )! = Find (V) // if no loop is formed {ans [ai] = I; AI ++; If (edges [I]. w> maxedge) maxedge = edges [I]. w; num ++; Union (u, v); // merged} If (Num> = n-1) Break ;}} int main () {While (CIN> N> m) {for (INT I = 1; I <= m; I ++) {CIN> edges [I]. u> edges [I]. v> edges [I]. w;} qsort (edges + 1, m, sizeof (edges [0]), CMP); maxedge = 0; num = 0; Kruskal (); cout <maxedge <Endl; cout <num <Endl; For (INT I = 0; I <num; I ++) {cout <edges [ans [I]. U <"" <edges [ans [I]. v <Endl ;}} return 0 ;}