[leet] Evaluate Division

Author: hyeonbinHur

허현빈/10주차/evaluate division.js

@@ -0,0 +1,45 @@
+var calcEquation = function(equations, values, queries) {
+  const graph = new Map();
+
+  const addEdge = (from, to, w) => {
+    if (!graph.has(from)) graph.set(from, []);
+    
+    graph.get(from).push([to, w]);
+  };
+
+  for (let i = 0; i < equations.length; i++) {
+    const [a, b] = equations[i];
+    const v = values[i];
+    addEdge(a, b, v);
+    addEdge(b, a, 1 / v);
+  }
+
+  const bfs = (start, end) => {
+    if (!graph.has(start) || !graph.has(end)) return -1;
+    if (start === end) return 1;
+
+    const q = [[start, 1]];
+    const visited = new Set([start]);
+
+    while (q.length) {
+      const [cur, prod] = q.shift();
+      if (cur === end) return prod;
+
+      for (const [next, w] of graph.get(cur)) {
+        if (visited.has(next)) continue;
+        visited.add(next);
+        q.push([next, prod * w]);
+      }
+    }
+    return -1;
+  };
+
+  const ans = new Array(queries.length);
+  for (let i = 0; i < queries.length; i++) {
+    const [s, t] = queries[i];
+    ans[i] = bfs(s, t);
+  }
+  return ans;
+};
+
+calcEquation([["a","b"],["b","c"]], [2.0,3.0], [["a","c"],["b","a"],["a","e"],["a","a"],["x","x"]])

허현빈/10주차/evaluate division/evaludate division1.js

@@ -0,0 +1,44 @@
+var calcEquation = function(equations, values, queries) {
+    const graph = new Map()
+
+    const addEdgs = (from, to, w) =>{
+        if(!graph.has(from)) graph.set(from, [])
+        graph.get(from).push([to,w])
+    }
+    for(let i = 0; i < equations.length; i++){
+        const [from, to] = equations[i]
+        const val = values[i]
+        addEdgs(from, to, val)
+        addEdgs(to, from, 1/val)
+    }
+    const bfs = (start, end) =>{
+        if(!graph.has(start) || !graph.has(end)) return -1
+        if(start === end) return 1
+        const q = [[start, 1]]
+
+        const visited = new Set([start])
+
+        while(q.length){
+            const [cur, prod] = q.shift()
+            if(cur === end) return prod
+            for(const [next, w] of graph.get(cur)){
+                if(visited.has(next)) continue
+                visited.add(next)
+                q.push([next, prod*w])
+            }
+        }
+        return -1
+    }
+    
+    const ans = new Array(queries.length)
+    for(let i = 0 ; i < queries.length; i++){  
+        const [s,t] = queries[i]
+        ans[i] = bfs(s,t)
+    }
+    console.log(graph)
+    console.log(ans)
+    return ans
+
+
+};
+calcEquation([["a","b"],["b","c"]], [2.0,3.0], [["a","c"],["b","a"],["a","e"],["a","a"],["x","x"]])

허현빈/10주차/evaluate division/evaludate division2.js

@@ -0,0 +1,38 @@
+var calcEquation = function(equations, values, queries) {
+    const graph = new Map()
+
+    const addNode = (from, to, w)=>{
+        if(!graph.has(from)) graph.set(from, [])
+        graph.get(from).push(to, w)
+    }
+    for(let i = 0 ; i < equations.length; i++){
+        const [from, to] = equstions[i]
+        const val = values[i]
+        addNode(from, to, val)
+        addNode(to, from, 1/val)
+    }
+    const bfs = (start, end) =>{
+        if(start === end) return 1
+        if(!graph.has(start) || !graph.has(end)) return -1
+        const q= [[start ,1]]
+        const visit = new Set()
+        while(q.length){
+            const [cur, w] = q.shift()
+            if(cur === end) return w
+
+            for(const [next, cw] of graph.get(cur)){
+                if(visit.has(next)) continue
+                visit.add(next)
+                q.push([next, w*cw])
+            }
+        }
+        return -1
+    }
+
+    const ans = [];
+    for(let i = 0; i <queries.length; i++){
+        const [s,t] =queries[i]
+        ans.push(bfs(s,t))
+    }
+    return ans
+};

허현빈/10주차/number of island.js

@@ -0,0 +1,33 @@
+/**
+ * @param {character[][]} grid
+ * @return {number}
+ */
+var numIslands = function(grid) {
+    const map = grid.map((e) => e.map((e2) => Number(e2)))
+    const dir =[[1,0], [-1,0], [0,1], [0,-1]]
+    const bfs = (row, col) =>{
+        map[row][col] = 0
+        const q = [[row, col]]
+        while(q.length){
+            const [curY, curX] = q.shift()
+            for(let i = 0; i < 4; i++){
+                const ny = curY + dir[i][0]
+                const nx = curX  + dir[i][1]
+                if(ny >= 0 && ny < map.length && nx >= 0 && nx < map[0].length&& map[ny][nx] === 1){
+                    map[ny][nx] = 0
+                    q.push([ny,nx])
+                }
+            }            
+        }
+    }
+    let ans = 0
+    for(let i = 0 ; i < map.length; i++){
+        for(let j = 0; j< map[0].length; j++){
+            if(map[i][j] === 1){
+                ans++
+                bfs(i,j)
+            }
+        }
+    }
+    return ans
+};