1+ function MinimumSpanningTree ( graph ) {
2+
3+ this . graph = graph ;
4+
5+ var INF = Number . MAX_SAFE_INTEGER ;
6+
7+ var minKey = function ( key , visited ) {
8+ // Initialize min value
9+ var min = INF , minIndex ;
10+
11+ for ( var v = 0 ; v < this . graph . length ; v ++ ) {
12+ if ( visited [ v ] == false && key [ v ] < min ) {
13+ min = key [ v ] ;
14+ minIndex = v ;
15+ }
16+ }
17+
18+ return minIndex ;
19+ } ;
20+
21+ this . prim = function ( ) {
22+ var parent = [ ] ,
23+ key = [ ] ,
24+ visited = [ ] ,
25+ length = this . graph . length ,
26+ i ;
27+
28+ for ( i = 0 ; i < length ; i ++ ) {
29+ key [ i ] = INF ;
30+ visited [ i ] = false ;
31+ }
32+
33+ key [ 0 ] = 0 ;
34+ parent [ 0 ] = - 1 ;
35+
36+ for ( i = 0 ; i < length - 1 ; i ++ ) {
37+ var u = minKey ( key , visited ) ;
38+ visited [ u ] = true ;
39+
40+ for ( var v = 0 ; v < length ; v ++ ) {
41+ if ( this . graph [ u ] [ v ] && visited [ v ] == false && this . graph [ u ] [ v ] < key [ v ] ) {
42+ parent [ v ] = u ;
43+ key [ v ] = this . graph [ u ] [ v ] ;
44+ }
45+ }
46+ }
47+
48+ return parent ;
49+ } ;
50+
51+ var find = function ( i , parent ) {
52+ while ( parent [ i ] ) {
53+ i = parent [ i ] ;
54+ }
55+ return i ;
56+ } ;
57+
58+ var union = function ( i , j , parent ) {
59+ if ( i != j ) {
60+ parent [ j ] = i ;
61+ return true ;
62+ }
63+ return false ;
64+ } ;
65+
66+ var initializeCost = function ( ) {
67+ var cost = [ ] , length = this . graph . length ;
68+ for ( var i = 0 ; i < length ; i ++ ) {
69+ cost [ i ] = [ ] ;
70+ for ( var j = 0 ; j < length ; j ++ ) {
71+ if ( this . graph [ i ] [ j ] == 0 ) {
72+ cost [ i ] [ j ] = INF ;
73+ } else {
74+ cost [ i ] [ j ] = this . graph [ i ] [ j ] ;
75+ }
76+ }
77+ }
78+ return cost ;
79+ } ;
80+
81+ this . kruskal = function ( ) {
82+
83+ var length = this . graph . length ,
84+ parent = [ ] , cost ,
85+ ne = 0 , a , b , u , v , i , j , min ;
86+
87+ cost = initializeCost ( ) ;
88+
89+ while ( ne < length - 1 ) {
90+
91+ for ( i = 0 , min = INF ; i < length ; i ++ ) {
92+ for ( j = 0 ; j < length ; j ++ ) {
93+ if ( cost [ i ] [ j ] < min ) {
94+ min = cost [ i ] [ j ] ;
95+ a = u = i ;
96+ b = v = j ;
97+ }
98+ }
99+ }
100+
101+ u = find ( u , parent ) ;
102+ v = find ( v , parent ) ;
103+
104+ if ( union ( u , v , parent ) ) {
105+ ne ++ ;
106+ }
107+
108+ cost [ a ] [ b ] = cost [ b ] [ a ] = INF ;
109+ }
110+
111+ return parent ;
112+ }
113+ }
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