https://codility.com/demo/take-sample-test/count_div 此题比较简单,是在O(1)时间里求区间[A,B]里面能被K整除的数字,那么就计算一下就能得到. int solution(int A, int B, int K) { // write your code in C++11 int diff = (B-A+1); int result = diff / K; for (int i = A + result * K; i <= B; i++)…