1- const initializeGraph = ( n ) => {
2- let G = [ ]
3- for ( let i = 0 ; i < n ; i ++ ) {
4- G . push ( [ ] )
5- }
6- return G
7- }
8- const addEdgeToG = ( G , Edges ) => {
9- for ( const [ u , v ] of Edges ) {
10- G [ u ] . push ( v )
11- G [ v ] . push ( u )
12- }
13- }
141/**
152 * @param {number } n
163 * @param {number[][] } edges
174 * @param {number } time
185 * @param {number } change
196 * @return {number }
207 */
21- const secondMinimum = ( n , edges , time , change ) => {
8+ var secondMinimum = function ( n , edges , time , change ) {
229 let adj = initializeGraph ( n + 1 )
2310 addEdgeToG ( adj , edges )
2411 let cost = initializeGraph ( n + 1 )
25- let pq = new MinPriorityQueue ( { priority : ( x ) => x [ 0 ] } )
26- pq . enqueue ( [ 0 , 1 ] )
12+ let pq = new PQ ( ( a , b ) => a [ 0 ] < b [ 0 ] )
13+ pq . push ( [ 0 , 1 ] )
2714 let green = 2 * change
2815 while ( pq . size ( ) ) {
29- let cur = pq . dequeue ( ) . element
16+ let cur = pq . pop ( )
3017 let [ t , node ] = cur
3118 if ( cost [ node ] . length == 2 ) continue
3219 let nextT =
@@ -45,9 +32,89 @@ const secondMinimum = (n, edges, time, change) => {
4532 continue
4633 }
4734 }
48- for ( const next_node of adj [ node ] ) pq . enqueue ( [ nextT + time , next_node ] )
35+ for ( const next_node of adj [ node ] ) pq . push ( [ nextT + time , next_node ] )
4936 }
5037 return cost [ n ] [ 1 ]
38+ } ;
39+ function initializeGraph ( n ) {
40+ let G = [ ]
41+ for ( let i = 0 ; i < n ; i ++ ) {
42+ G . push ( [ ] )
43+ }
44+ return G
45+ }
46+ function addEdgeToG ( G , Edges ) {
47+ for ( const [ u , v ] of Edges ) {
48+ G [ u ] . push ( v )
49+ G [ v ] . push ( u )
50+ }
51+ }
52+ class PQ {
53+ constructor ( comparator = ( a , b ) => a > b ) {
54+ this . heap = [ ]
55+ this . top = 0
56+ this . comparator = comparator
57+ }
58+ size ( ) {
59+ return this . heap . length
60+ }
61+ isEmpty ( ) {
62+ return this . size ( ) === 0
63+ }
64+ peek ( ) {
65+ return this . heap [ this . top ]
66+ }
67+ push ( ...values ) {
68+ values . forEach ( ( value ) => {
69+ this . heap . push ( value )
70+ this . siftUp ( )
71+ } )
72+ return this . size ( )
73+ }
74+ pop ( ) {
75+ const poppedValue = this . peek ( )
76+ const bottom = this . size ( ) - 1
77+ if ( bottom > this . top ) {
78+ this . swap ( this . top , bottom )
79+ }
80+ this . heap . pop ( )
81+ this . siftDown ( )
82+ return poppedValue
83+ }
84+ replace ( value ) {
85+ const replacedValue = this . peek ( )
86+ this . heap [ this . top ] = value
87+ this . siftDown ( )
88+ return replacedValue
89+ }
90+ 91+ parent = ( i ) => ( ( i + 1 ) >>> 1 ) - 1
92+ left = ( i ) => ( i << 1 ) + 1
93+ right = ( i ) => ( i + 1 ) << 1
94+ greater = ( i , j ) => this . comparator ( this . heap [ i ] , this . heap [ j ] )
95+ swap = ( i , j ) => ( [ this . heap [ i ] , this . heap [ j ] ] = [ this . heap [ j ] , this . heap [ i ] ] )
96+ siftUp = ( ) => {
97+ let node = this . size ( ) - 1
98+ while ( node > this . top && this . greater ( node , this . parent ( node ) ) ) {
99+ this . swap ( node , this . parent ( node ) )
100+ node = this . parent ( node )
101+ }
102+ }
103+ siftDown = ( ) => {
104+ let node = this . top
105+ while (
106+ ( this . left ( node ) < this . size ( ) && this . greater ( this . left ( node ) , node ) ) ||
107+ ( this . right ( node ) < this . size ( ) && this . greater ( this . right ( node ) , node ) )
108+ ) {
109+ let maxChild =
110+ this . right ( node ) < this . size ( ) &&
111+ this . greater ( this . right ( node ) , this . left ( node ) )
112+ ? this . right ( node )
113+ : this . left ( node )
114+ this . swap ( node , maxChild )
115+ node = maxChild
116+ }
117+ }
51118}
52119
53120// another
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