leetcode 12题 数字转罗马数字 答案一:我的代码 代码本地运行完全正确,在线运行出错 class Solution { public: string intToRoman(int num) { //哈希表初始化: unordered_map<int,char>hash; string str_initial1="IXCM"; string str_initial2="VLD"; ; ;i<=;i*=){ hash[i]=str_initi…

Implement the following operations of a stack using queues. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the top element. empty() -- Return whether the stack is empty. Notes: You may assume that…

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the top element. getMin() -- Retrieve the minimum e…

原标题:https://oj.leetcode.com/problems/min-stack/ Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the…

Design a max stack that supports push, pop, top, peekMax and popMax. push(x) -- Push element x onto stack. pop() -- Remove the element on top of the stack and return it. top() -- Get the element on the top. peekMax() -- Retrieve the maximum element i…

话说博主在写Max Chunks To Make Sorted II这篇帖子的解法四时,写到使用单调栈Monotone Stack的解法时,突然脑中触电一般,想起了之前曾经在此贴LeetCode All in One 题目讲解汇总(持续更新中...)的留言区中说要写单调栈的总结帖,当时答应了要写,就去LeetCode上看标记为Stack的题,可是发现有好多题,而且很多用的不是单调栈,于是博主一个一个的看了起来,但是无奈太多了,一直没有时间全部看完,就一直没有动笔写.虽说时间就像那啥,挤挤总会有的…

原题链接在这里:https://leetcode.com/problems/max-stack/description/ 题目: Design a max stack that supports push, pop, top, peekMax and popMax. push(x) -- Push element x onto stack. pop() -- Remove the element on top of the stack and return it. top() -- Get th…

Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000 For example, two is written as II in Roman numeral, just two one's added together. Twelve is written as, XII, which i…

Leetcode第12题,整数转罗马数字,难度中等 整个题目比较好理解,难度也不大,就算不过脑子,用一串if也基本上可以解决问题,比如 /** 执行用时:6ms,在所有 Java 提交中击败了52.61%的用户 内存消耗:40.3 MB, 在所有 Java 提交中击败了5.00%的用户 */ public String intToRoman(int num) { StringBuilder sb = new StringBuilder(); if(num < 1 || num > 3999)…

12. 整数转罗马数字 罗马数字包含以下七种字符: I, V, X, L,C,D 和 M. 字符 数值 I 1 V 5 X 10 L 50 C 100 D 500 M 1000 例如, 罗马数字 2 写做 II ,即为两个并列的 1.12 写做 XII ,即为 X + II . 27 写做 XXVII, 即为 XX + V + II . 通常情况下,罗马数字中小的数字在大的数字的右边.但也存在特例,例如 4 不写做 IIII,而是 IV.数字 1 在数字 5 的左边,所表示的数等于大数 5 减小…