CC150

网址：https://www.nowcoder.com/ta/cracking-the-coding-interview?query=&asc=true&order=&page=1

 1 class Different {
 2 public:
 3     bool checkDifferent(string iniString) {
 4         // write code here
 5         int len = iniString.size();
 6         if (len > 256)
 7             return false;
 8         
 9         int cnt[255] = {0};
10         for(int i = 0; i < len; i++)
11         {
12             int j = iniString[i];
13             if (cnt[j])
14                 return false;
15             else
16                 cnt[j] = 1;
17         }
18         return true;
19     }
20 };

View Code

 1 class Different {
 2 public:
 3     bool checkDifferent(string iniString) {
 4         // write code here
 5         int len = iniString.size();
 6         if (len > 256)
 7             return false;
 8         
 9         for(int i = 0; i < len; i++)
10         {
11             for (int j = i + 1; j < len; j++)
12             {
13                 if (iniString[i] == iniString[j])
14                     return false;
15             }
16         }
17         return true;
18     }
19 };

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1.2原串翻转

 1 class Reverse {
 2 public:
 3     string reverseString(string iniString) 
 4     {
 5         // write code here
 6         char ch;
 7         int len = iniString.size();
 8         for(int i = 0; i < len / 2; i++)
 9         {
10             ch = iniString[i];
11             iniString[i] = iniString[len - 1 - i];
12             iniString[len - 1 - i] = ch;
13         }
14         return iniString;
15     }
16 };

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1 class Reverse {
2 public:
3     string reverseString(string iniString) 
4     {
5         // write code here
6         reverse(iniString.begin(), iniString.end());
7         return iniString;
8     }
9 };

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1.3确定两串乱序同构

 1 class Same {
 2 public:
 3     bool checkSam(string stringA, string stringB) {
 4         // write code here
 5         int len1 = stringA.size();
 6         int len2 = stringB.size();
 7         if(len1 != len2)
 8             return false;
 9         
10         int cnt[257] = {0};
11         for(int i = 0; i < len1; i++)
12         {
13             cnt[stringA[i]]++;
14             cnt[stringB[i]]--;
15         }     
16        for(int i = 0; i < 256; i++)
17        {
18            if (cnt[i])
19                return false;
20        }
21         
22        return true;  
23     }
24 };

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1.4空格替换

 1 class Replacement {
 2 public:
 3     string replaceSpace(string iniString, int length) {
 4         // write code here
 5         int cnt = 0;
 6         
 7         for (int i = 0; i < length; i++)
 8         {
 9             if (iniString[i] == ' ')
10                 cnt++;
11         }
12         cnt = cnt * 2 + length;
13         iniString.resize(cnt);
14         cnt--;
15         
16         for (int i = length - 1; i >= 0; i--)
17         {
18             if (iniString[i] == ' ')
19             {
20                 iniString[cnt--] = '0';
21                 iniString[cnt--] = '2';
22                 iniString[cnt--] = '%';
23             }
24             else
25                 iniString[cnt--] = iniString[i];
26         }
27         
28         return iniString;
29     }
30 };

View Code

1.5基本字符串压缩

 1 class Zipper {
 2 public:
 3     string zipString(string iniString) {
 4         // write code here
 5         int len = iniString.size();
 6         string res;
 7         int cnt = 1;
 8         char ch = iniString[0];
 9         
10         for (int i = 1; i < len; i++)
11         {
12             if (iniString[i] == ch)
13             {
14                 cnt++;
15             }
16             else
17             {
18                 res += ch;
19                 res += to_string(cnt);
20                 cnt = 1;
21                 ch = iniString[i];
22             }
23         }
24         res += ch;
25         res += to_string(cnt);
26         
27         if (res.size() >= len)
28             return iniString;
29         else
30             return res;
31     }
32 };

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1.6像素翻转

 1 class Transform {
 2 public:
 3     vector<vector<int> > transformImage(vector<vector<int> > mat, int n) {
 4         // write code here
 5         int t;
 6         
 7         for (int i = 0; i < n / 2; i++)
 8         {
 9             for (int j = 0; j < n; j++)
10             {
11                 t = mat[i][j];
12                 mat[i][j] = mat[n - 1- i][j];
13                 mat[n - 1- i][j] = t;
14             }
15         }
16         
17         for (int i = 0; i < n; i++)
18         {
19             for (int j = 0; j < i; j++)
20             {
21                 t = mat[i][j];
22                 mat[i][j] = mat[j][i];
23                 mat[j][i] = t;
24             }
25         }
26         return mat;
27     }
28 };

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1.7清除行列

 1 class Clearer {
 2 public:
 3     vector<vector<int> > clearZero(vector<vector<int> > mat, int n) {
 4         // write code here
 5         int row = 0;
 6         int column = 0;
 7         for (int i = 0; i < n; i++)
 8         {
 9             if (mat[i][0] == 0)
10             {
11                 column = 1;
12                 break;
13             }
14         }
15         for (int i = 0; i < n; i++)
16         {
17             if (mat[0][i] == 0)
18             {
19                 row = 1;
20                 break;
21             }
22         }
23         
24         for (int i = 1; i < n; i++)
25         {
26             for (int j = 1; j < n; j++)
27             {
28                 if (mat[i][j] == 0)
29                 {
30                     mat[0][j] = 0;
31                     mat[i][0] = 0;
32                 }
33             }
34         }
35         
36         for (int i = 1; i < n; i++)
37         {
38             for (int j = 1; j < n; j++)
39             {
40                 if (mat[i][0] == 0 || mat[0][j] == 0)
41                 {
42                     mat[i][j] = 0;
43                 }
44             }
45         }
46         
47         if (column)
48         {
49             for (int i = 0; i < n; i++)
50                 mat[i][0] = 0;
51         }
52         if (row)
53         {
54             for (int i = 0; i < n; i++)
55                 mat[0][i] = 0;
56         }
57         
58         return mat;
59     }
60 };

View Code

 1 class Clearer {
 2 public:
 3     vector<vector<int> > clearZero(vector<vector<int> > mat, int n) {
 4         // write code here
 5         int row = 0;
 6         for (int i = 0; i < n; i++)
 7         {
 8             if (mat[0][i] == 0)
 9             {
10                 row = 1;
11                 break;
12             }
13         }
14         
15         for (int i = 1; i < n; i++)
16         {
17             for (int j = 0; j < n; j++)
18             {
19                 if (mat[i][j] == 0)
20                 {
21                     mat[0][j] = 0;
22                     mat[i][0] = 0;
23                 }
24             }
25         }
26         
27         for (int i = n - 1; i >= 1; i--)
28         {
29             for (int j = n - 1; j >= 0; j--)
30             {
31                 if (mat[i][0] == 0 || mat[0][j] == 0)
32                 {
33                     mat[i][j] = 0;
34                 }
35             }
36         }
37         
38         if (row)
39         {
40             for (int i = 0; i < n; i++)
41                 mat[0][i] = 0;
42         }
43         
44         return mat;
45     }
46 };

View Code

1.8翻转子串

 1 class ReverseEqual {
 2 public:
 3     bool checkReverseEqual(string s1, string s2) {
 4         // write code here
 5         sort(s1.begin(), s1.end());
 6         sort(s2.begin(), s2.end());
 7         
 8         return s1 == s2;
 9     }
10 };

View Code

 1 class ReverseEqual {
 2 public:
 3     bool checkReverseEqual(string s1, string s2) {
 4         // write code here
 5         int len1 = s1.size();
 6         int len2 = s2.size();
 7         if (len1 != len2)
 8             return false;
 9         
10         int cnt[257] = {0};
11         for (int i = 0; i < len1; i++)
12         {
13             cnt[s1[i]]++;
14             cnt[s2[i]]--;
15         }
16         for (int i = 0; i < 256; i++)
17         {
18             if (cnt[i])
19                 return false;
20         }
21         
22         return true;
23     }
24 };

View Code

 1 class ReverseEqual {
 2 public:
 3     bool checkReverseEqual(string s1, string s2) {
 4         // write code here
 5         int len1 = s1.size();
 6         int len2 = s2.size();
 7         if (len1 != len2)
 8             return false;
 9         
10         string s = s1 + s1;
11         if (s.find(s2) == string::npos)
12             return false;
13         else
14             return true;
15     }
16 };

View Code

2.2链表中倒数第k个结点

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) :
 6             val(x), next(NULL) {
 7     }
 8 };*/
 9 class Solution {
10 public:
11     ListNode* FindKthToTail(ListNode* pListHead, unsigned int k) {
12         int i = 1;
13         ListNode* slow = pListHead;
14         ListNode* fast = pListHead;
15         
16         while (i <= k && fast)
17         {
18             i++;
19             fast = fast->next;
20         }
21         
22         if (i <= k)
23             return NULL;
24         else
25         {
26             while (fast)
27             {
28                 fast = fast->next;
29                 slow = slow->next;
30             }
31             return slow;
32         }
33     }
34 };

View Code

2.3访问单个节点的删除

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) : val(x), next(NULL) {}
 6 };*/
 7 class Remove {
 8 public:
 9     bool removeNode(ListNode* pNode) {
10         // write code here
11         if (pNode == NULL || pNode->next == NULL)
12             return false;
13         
14         *pNode = *(pNode->next);
15         return true;
16     }
17 };

View Code

2.4链表分割

2.5链式A+B

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) : val(x), next(NULL) {}
 6 };*/
 7 class Plus {
 8 public:
 9     ListNode* plusAB(ListNode* a, ListNode* b) {
10         // write code here
11         ListNode* head = new ListNode(0);
12         ListNode* p = head;
13         int jin = 0;
14         int x, y, sum;
15         while (a || b || jin)
16         {
17             x = (a == NULL) ? 0 : a->val;
18             y = (b == NULL) ? 0 : b->val;
19             sum = jin + x + y;
20             p->next = new ListNode(sum % 10);
21             jin = sum / 10;
22             a = (a == NULL) ? NULL : a->next;
23             b = (b == NULL) ? NULL : b->next;
24             p = p->next;
25         }
26         p->next = NULL;
27         return head->next;
28     }
29 };

View Code

2.7回文链表

3.3集合栈

3.5用两个栈实现队列

 1 class Solution
 2 {
 3 public:
 4     void push(int node) {
 5         stack1.push(node);
 6     }
 7 
 8     int pop() {
 9         int num;
10         if (stack2.empty())
11         {
12             while (!stack1.empty())
13             {
14                 stack2.push(stack1.top());
15                 stack1.pop();
16             }
17         }
18         
19         num = stack2.top();
20         stack2.pop();
21         return num;
22     }
23 
24 private:
25     stack<int> stack1;
26     stack<int> stack2;
27 };

View Code

3.6双栈排序

4.1二叉树平衡检查

 1 /*
 2 struct TreeNode {
 3     int val;
 4     struct TreeNode *left;
 5     struct TreeNode *right;
 6     TreeNode(int x) :
 7             val(x), left(NULL), right(NULL) {
 8     }
 9 };*/
10 
11 class Balance {
12 public:
13     bool flag = 1;
14     int dfs(TreeNode* root)
15     {
16         if (!flag)
17             return 0;
18         if (root == NULL)
19             return 0;
20         
21         int l = dfs(root->left);
22         int r = dfs(root->right);
23         if (abs(l - r) > 1)
24             flag = 0;
25         
26         return max(l, r) + 1;
27     }
28     bool isBalance(TreeNode* root) {
29         // write code here
30         if (root == NULL)
31             return true;
32         
33         dfs(root);
34         return flag;
35     }
36 };

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posted on 2017-08-18 10:03 dxy1993 阅读(247) 评论(0) 编辑收藏举报