摘要： http://www.geeksforgeeks.org/maximum-sum-such-that-no-two-elements-are-adjacent/ 1 #include 2 #include 3 #include 4 #include 5 #include 6 #include 7 #include 8 #include 9 using namespace std;10 11 int maxsum(int arr[], int n) {12 int insum = arr[0];13 int exsum = 0;14 for (int i ... 阅读全文

摘要： http://www.geeksforgeeks.org/array-rotation/O(n), O(1) 1 #include 2 #include 3 #include 4 #include 5 #include 6 #include 7 #include 8 #include 9 using namespace std;10 11 int gcd(int a, int b) {12 return b == 0? a : gcd(b, a % b);13 }14 15 void leftrotate(int arr[], int d, int n) {16 ... 阅读全文

摘要： http://www.geeksforgeeks.org/find-the-missing-number/1. use sum formula, O(n), O(1)2. use XOR, O(n), O(1)3. use counting sort, O(n), O(1), changing the array4. use negtive, O(n), O(1), chaning the array 1 #include 2 #include 3 #include 4 #include 5 #include 6 #include 7 #include 8 #include 9... 阅读全文