面试题51 数组中重复的数字

 1 class Solution {
 2 public:
 3     // Parameters:
 4     //        numbers:     an array of integers
 5     //        length:      the length of array numbers
 6     //        duplication: (Output) the duplicated number in the array number
 7     // Return value:       true if the input is valid, and there are some duplications in the array number
 8     //                     otherwise false
 9     bool duplicate(int numbers[], int length, int* duplication) {     
10         for(int i=0;i<length;i++){           
11             int j=numbers[i]%length;
12             numbers[j]+=length;
13             if(numbers[j]>=(2*length)){
14                 *duplication = numbers[j]%length;
15                 return true;
16             }                                 
17         }
18         return false;      
19     }
20 };