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DijkstraSmallestPath.js: Standardjs fixes (#147)

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Christian Clauss
2020-05-04 22:31:34 +02:00
committed by GitHub
parent ec89a904a2
commit 6483ecc427
1 changed files with 67 additions and 74 deletions
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95
maths/DijkstraSmallestPath.js
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@ -1,68 +1,63 @@
// starting at s // starting at s
function solve (graph, s) { function solve (graph, s) {
var solutions = {}; var solutions = {}
solutions[s] = []; solutions[s] = []
solutions[s].dist = 0; solutions[s].dist = 0
while (true) { while (true) {
var p = null; var p = null
var neighbor = null; var neighbor = null
var dist = Infinity; var dist = Infinity
for (var n in solutions) { for (var n in solutions) {
if(!solutions[n]) if (!solutions[n]) { continue }
continue var ndist = solutions[n].dist
var ndist = solutions[n].dist; var adj = graph[n]
var adj = graph[n];
for (var a in adj) { for (var a in adj) {
if (solutions[a]) { continue }
if(solutions[a]) var d = adj[a] + ndist
continue;
var d = adj[a] + ndist;
if (d < dist) { if (d < dist) {
p = solutions[n]
p = solutions[n]; neighbor = a
neighbor = a; dist = d
dist = d;
} }
} }
} }
// no more solutions // no more solutions
if (dist === Infinity) { if (dist === Infinity) {
break; break
} }
// extend parent's solution path // extend parent's solution path
solutions[neighbor] = p.concat(neighbor); solutions[neighbor] = p.concat(neighbor)
// extend parent's cost // extend parent's cost
solutions[neighbor].dist = dist; solutions[neighbor].dist = dist
} }
return solutions; return solutions
} }
// create graph // create graph
var graph = {}; var graph = {}
var layout = { var layout = {
'R': ['2'], R: ['2'],
'2': ['3','4'], 2: ['3', '4'],
'3': ['4','6','13'], 3: ['4', '6', '13'],
'4': ['5','8'], 4: ['5', '8'],
'5': ['7','11'], 5: ['7', '11'],
'6': ['13','15'], 6: ['13', '15'],
'7': ['10'], 7: ['10'],
'8': ['11','13'], 8: ['11', '13'],
'9': ['14'], 9: ['14'],
'10': [], 10: [],
'11': ['12'], 11: ['12'],
'12': [], 12: [],
'13': ['14'], 13: ['14'],
'14': [], 14: [],
'15': [] 15: []
} }
// convert uni-directional to bi-directional graph // convert uni-directional to bi-directional graph
@ -78,26 +73,24 @@ var layout = {
// }; // };
for (var id in layout) { for (var id in layout) {
if(!graph[id]) if (!graph[id]) { graph[id] = {} }
graph[id] = {};
layout[id].forEach(function (aid) { layout[id].forEach(function (aid) {
graph[id][aid] = 1; graph[id][aid] = 1
if(!graph[aid]) if (!graph[aid]) { graph[aid] = {} }
graph[aid] = {}; graph[aid][id] = 1
graph[aid][id] = 1; })
});
} }
// choose start node // choose start node
var start = '10'; var start = '10'
// get all solutions // get all solutions
var solutions = solve(graph, start); var solutions = solve(graph, start)
console.log("From '"+start+"' to"); console.log("From '" + start + "' to")
// display solutions // display solutions
for (var s in solutions) { for (var s in solutions) {
if(!solutions[s]) continue; if (!solutions[s]) continue
console.log(" -> " + s + ": [" + solutions[s].join(", ") + "] (dist:" + solutions[s].dist + ")"); console.log(' -> ' + s + ': [' + solutions[s].join(', ') + '] (dist:' + solutions[s].dist + ')')
} }
// From '10' to // From '10' to