数据结构与算法--栈(TypeScript)

定义栈

Stack.ts

interface IStack<T> {
  push(element: T): void;
  pop(): T | undefined;
  peek(): T | undefined;
  isEmpty(): boolean;
  size(): number;
}
class ArrayStack<T = any> implements IStack<T> {
  private stack: T[];
  constructor() {
    this.stack = [];
  }
  push(element: T): void {
    this.stack.push(element);
  }
  pop(): T | undefined {
    return this.stack.pop();
  }
  peek(): T | undefined {
    return this.stack[this.stack.length - 1];
  }
  isEmpty(): boolean {
    return this.stack.length === 0;
  }
  size(): number {
    return this.stack.length;
  }
}
export { ArrayStack };

应用

十进制转二进制

DecimalToBinary.ts

import { ArrayStack } from "./Stack";
function DecimalToBinary(decimal: number): string {
  const stack = new ArrayStack<number>();
  while (decimal > 0) {
    let result = decimal % 2;
    stack.push(result);
    decimal = Math.floor(decimal / 2);
  }
  let binary = "";
  while (!stack.isEmpty()) {
    binary += stack.pop();
  }
  return binary;
}

console.log(DecimalToBinary(15))

有效的括号

IsValid.ts

import { ArrayStack } from "./Stack";
function isValid(str: string): boolean {
  let stack = new ArrayStack<string>();
  for (let i = 0; i < str.length; i++) {
    let c = str[i];
    switch (c) (c) {
      case "(":
        stack.push(")");
        break;
      case "{":
        stack.push("}");
        break;
      case "[":
        stack.push("]");
        break;
      default:
        if (c != stack.pop()) return false;
        break;
    }
  }
  if (!stack.isEmpty()) {
    return false;
  }
  return true;
}
console.log(isValid("()(){}[]"));