A self-dividing number is a number that is divisible by every digit it contains.
For example, 128 is a self-dividing number because 128 % 1 == 0, 128 % 2 == 0, and 128 % 8 == 0.
Also, a self-dividing number is not allowed to contain the digit zero.
Given a lower and upper number bound, output a l......
Given an integer (signed 32 bits), write a function to check whether it is a power of 4.
Example:
Given num = 16, return true. Given num = 5, return false.
Follow up: Could you solve it without loops/recursion?
bool isPowerOfFour(int num)
{
return !(num & (num - 1)) && (num & 0......
Given two non-empty binary trees s and t, check whether tree t has exactly the same structure and node values with a subtree of s. A subtree of s is a tree consists of a node in s and all of this node's descendants. The tree s could also be considered as a subtree of itself.
递归实现，代码有点美😄
/**
*......
Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.
Example 1
Input:
Output: 2
Example 2
Input:
Output: 8
一个“简单”的问题，深思之后似乎并没有那么简单。
最开始的版本：
int missingNumber(int* nums, int numsSize)
{
int sum = 0;
sum = numsSize *(n......
Given an integer, write a function to determine if it is a power of two.
我的常规解法：对于INT_MIN的话是-2147483648的话恰好也满足二进制位中只有一个1的情况，因此应该排除，然后统计n中1的个数， 如果为1则返回true;
bool isPowerOfTwo(int n)
{
if(INT_MIN == n)
return false;
int cnt = 0;
while(n)
{
n = n &(n-1);
cnt++;
}
return (cnt ==1 )? true:false......
Given two strings s and t which consist of only lowercase letters.
String t is generated by random shuffling string s and then add one more letter at a random position.
Find the letter that was added in t.
Input:
s = "abcd"
t = "abcde"
Output:
e
Explanation:
'e......
Given a List of words, return the words that can be typed using letters of alphabet on only one row's of American keyboard like the image below.
int insameline(char *str, int *hash)
{......
Given a linked list, swap every two adjacent nodes and return its head.
For example,
Given 1->2->3->4, you should return the list as 2->1->4->3.
Your algorithm should use only constant space. You may not modify the values in the list, only nodes itself can be changed.
/*......
Given a positive integer, output its complement number. The complement strategy is to flip the bits of its binary representation.
Note:
The given integer is guaranteed to fit within the range of a 32-bit signed integer.
You could assume no leading zero bit in the integer’s binary representatio......
Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
Supposed the linked list is 1 -> 2 -> 3 -> 4 and you are given the third node with value 3, the linked list should become 1 -> 2 -> 4 after calling your function.
这道题有一个限制......