Merge pull request #2758 from suinming/kamacoder-47-js

feat: 47. 参加科学大会新增js解法

Author: youngyangyang04

problems/kamacoder/0047.参会dijkstra朴素.md

@@ -869,6 +869,65 @@ if __name__ == "__main__":
 
 ### Javascript
 
+```js
+function dijkstra(grid, start, end) {
+    const visited = Array.from({length: end + 1}, () => false)
+    const minDist = Array.from({length: end + 1}, () => Number.MAX_VALUE)
+    minDist[start] = 0
+    
+    for (let i = 1 ; i < end + 1 ; i++) {
+        let cur = -1
+        let tempMinDist = Number.MAX_VALUE
+        // 1. 找尋與起始點距離最近且未被訪的節點
+        for (let j = 1 ; j < end + 1 ; j++) {
+            if (!visited[j] && minDist[j] < tempMinDist) {
+                cur = j
+                tempMinDist = minDist[j]
+            }
+        }
+        if (cur === -1) break;
+        
+        // 2. 更新節點狀態為已拜訪
+        visited[cur] = true
+        
+        // 3. 更新未拜訪節點與起始點的最短距離
+        for (let j = 1 ; j < end + 1 ; j++) {
+            if(!visited[j] && grid[cur][j] != Number.MAX_VALUE 
+                && grid[cur][j] + minDist[cur] < minDist[j]
+            ) {
+                minDist[j] = grid[cur][j] + minDist[cur]
+            }
+        }
+    }
+    
+    return minDist[end] === Number.MAX_VALUE ? -1 : minDist[end]
+}
+
+
+async function main() {
+    // 輸入
+    const rl = require('readline').createInterface({ input: process.stdin })
+    const iter = rl[Symbol.asyncIterator]()
+    const readline = async () => (await iter.next()).value
+    const [n, m] = (await readline()).split(" ").map(Number)
+    const grid = Array.from({length: n + 1}, 
+        () => Array.from({length:n + 1}, () => Number.MAX_VALUE))
+    for (let i = 0 ; i < m ; i++) {
+        const [s, e, w] = (await readline()).split(" ").map(Number)
+        grid[s][e] = w
+    }
+    
+    // dijkstra
+    const result = dijkstra(grid, 1, n)
+    
+    // 輸出
+    console.log(result)
+}
+
+
+main()
+```
+
 ### TypeScript
 
 ### PhP