计数排序

class CountingSort {public:    int * countingSort(int* A, int n) {// write code hereint min_ = A[0];int max_ = A[0];for (int i = 0; i<n; i++){if (A[i]<min_){min_ = A[i];}if (A[i]>max_){max_ = A[i];}}int len = max_ - min_ + 1;int *B = new int[len+1];int *C = new int[n];memset(B,0,sizeof(int)*(len+1));memset(C,0,sizeof(int)*(n) );for (int i = 0; i<n; i++){B[A[i] - min_]++;}for (int i = 1; i <= len; i++){B[i]+= B[i - 1];}int j = 0;for (int i = 0; i<n; i++){C[B[A[i] - min_] - 1] = A[i];B[A[i]-min_]--;}return C;}};