Merge pull request #2358 from pzppzz/master

feat: 0332重新安排行程 添加JavaScript版本 处理对象key无序问题 0051.N皇后 更简洁清晰的javascript版本

problems/0051.N皇后.md

@@ -453,60 +453,66 @@ func isValid(n, row, col int, chessboard [][]string) bool {
 
 ### Javascript 
 ```Javascript
-var solveNQueens = function(n) {
+/**
-    function isValid(row, col, chessBoard, n) {
+ * @param {number} n
-
+ * @return {string[][]}
-        for(let i = 0; i < row; i++) {
+ */
-            if(chessBoard[i][col] === 'Q') {
+var solveNQueens = function (n) {
-                return false
+	const ans = [];
-            }
+	const path = [];
-        }
+	const matrix = new Array(n).fill(0).map(() => new Array(n).fill("."));
-
+	// 判断是否能相互攻击
-        for(let i = row - 1, j = col - 1; i >= 0 && j >= 0; i--, j--) {
+	const canAttack = (matrix, row, col) => {
-            if(chessBoard[i][j] === 'Q') {
+		let i;
-                return false
+		let j;
-            }
+		// 判断正上方和正下方是否有皇后
-        }
+		for (i = 0, j = col; i < n; i++) {
-
+			if (matrix[i][j] === "Q") {
-        for(let i = row - 1, j = col + 1; i >= 0 && j < n; i--, j++) {
+				return true;
-            if(chessBoard[i][j] === 'Q') {
+			}
-                return false
+		}
-            }
+		// 判断正左边和正右边是否有皇后
-        }
+		for (i = row, j = 0; j < n; j++) {
-        return true
+			if (matrix[i][j] === "Q") {
-    }
+				return true;
-
+			}
-    function transformChessBoard(chessBoard) {
+		}
-        let chessBoardBack = []
+		// 判断左上方是否有皇后
-        chessBoard.forEach(row => {
+		for (i = row - 1, j = col - 1; i >= 0 && j >= 0; i--, j--) {
-            let rowStr = ''
+			if (matrix[i][j] === "Q") {
-            row.forEach(value => {
+				return true;
-                rowStr += value
+			}
-            })
+		}
-            chessBoardBack.push(rowStr)
+         // 判断右上方是否有皇后
-        })
+		for (i = row - 1, j = col + 1; i >= 0 && j < n; i--, j++) {
-
+			if (matrix[i][j] === "Q") {
-        return chessBoardBack
+				return true;
-    }
+			}
-
+		}
-    let result = []
+		return false;
-    function backtracing(row,chessBoard) {
+	};
-        if(row === n) {
+	const backtrack = (matrix, row, col) => {
-            result.push(transformChessBoard(chessBoard))
+		if (path.length === matrix.length) {
-            return
+			ans.push(path.slice());
-        }
+			return;
-        for(let col = 0; col < n; col++) {
+		}
-            if(isValid(row, col, chessBoard, n)) {
+		for (let i = row; i < matrix.length; i++) {
-                chessBoard[row][col] = 'Q'
+			for (let j = col; j < matrix.length; j++) {
-                backtracing(row + 1,chessBoard)
+				// 当前位置会导致互相攻击 继续下一轮搜索
-                chessBoard[row][col] = '.'
+				if (canAttack(matrix, i, j)) {
-            }
+					continue;
-        }
+				}
-    }
+				matrix[i][j] = "Q";
-    let chessBoard = new Array(n).fill([]).map(() => new Array(n).fill('.'))
+				path.push(matrix[i].join(""));
-    backtracing(0,chessBoard)
+				// 另起一行搜索 同一行只能有一个皇后
-    return result
+				backtrack(matrix, i + 1, 0);
-    
+				matrix[i][j] = ".";
+				path.pop();
+			}
+		}
+	};
+	backtrack(matrix, 0, 0);
+	return ans;
 };
 ```
 

problems/0332.重新安排行程.md

@@ -562,6 +562,7 @@ func findItinerary(tickets [][]string) []string {
 ```
 
 ### Javascript 
+
 ```Javascript
 
 var findItinerary = function(tickets) {
@@ -605,6 +606,74 @@ var findItinerary = function(tickets) {
 
 ```
 
+**javascript版本二 处理对象key无序问题**
+
+```javascript
+/**
+ * @param {string[][]} tickets
+ * @return {string[]}
+ */
+var findItinerary = function (tickets) {
+	const ans = ["JFK"];
+	let map = {};
+	// 整理每个站点的终点站信息
+	tickets.forEach((t) => {
+		let targets = map[t[0]];
+		if (!targets) {
+			targets = { [t[1]]: 0 };
+			map[t[0]] = targets;
+		}
+		targets[t[1]] = (targets[t[1]] || 0) + 1;
+	});
+	// 按照key字典序排序对象
+	const sortObject = (obj) => {
+		const newObj = {};
+		const keys = Object.keys(obj);
+		keys.sort((k1, k2) => (k1 < k2 ? -1 : 1));
+		keys.forEach((key) => {
+			if (obj[key] !== null && typeof obj[key] === "object") {
+				newObj[key] = sortObject(obj[key]);
+			} else {
+				newObj[key] = obj[key];
+			}
+		});
+		return newObj;
+	};
+	const backtrack = (tickets, targets) => {
+		if (ans.length === tickets.length + 1) {
+			return true;
+		}
+		const target = targets[ans[ans.length - 1]];
+		// 没有下一站
+		if (!target) {
+			return false;
+		}
+		// 或者在这里排序
+		// const keyList = Object.keys(target).sort((k1, k2) => (k1 < k2 ? -1 : 1));
+		const keyList = Object.keys(target);
+		for (const key of keyList) {
+			// 判断当前站是否还能飞
+			if (target[key] > 0) {
+				target[key]--;
+				ans.push(key);
+				// 对象key有序 此时的行程就是字典序最小的 直接跳出
+				if (backtrack(tickets, targets)) {
+					return true;
+				}
+				target[key]++;
+				ans.pop();
+			}
+		}
+		return false;
+	};
+	map = sortObject(map);
+	backtrack(tickets, map);
+	return ans;
+};
+```
+
+
+
 ### TypeScript
 
 ```typescript
@@ -901,3 +970,4 @@ impl Solution {
 <a href="https://programmercarl.com/other/kstar.html" target="_blank">
   <img src="../pics/网站星球宣传海报.jpg" width="1000"/>
 </a>
+