C++ Memory Limit Exceeded when running small numbers

Question

I am making a code for a problem on Iceland.Kattis.Com called voff in which you have to calculate the number of dogs required to produce a certain frequency of barks.

There are N barks and each dog can bark up to once every K seconds. The first line of input contains N and K, the second line contains the times at which barks were heard.

I have made a python code which is almost fast enough to get 100 points but just a little bit shy of getting there. So I decided to write the same code but in C++ (clang 7.0.0-3~ubuntu0.18.04.1) and when I run any other test case than the first one I get Memeory Limit Exceeded.

I have tried using 'long long', 'unsigned long long' and 'int' but I get Memory Limit Exceeded on all of them.

#include <bits/stdc++.h>
using namespace std;


int main() {
  int N, K;
  vector<int> barks;
  vector<int> dogs;
  dogs.push_back(0);

  cin >> N >> K;
  for(int i = 0; i < N; i++){
    int inp;
    cin >> inp;
    barks.push_back(inp);
  }


  for(int bark : barks){
    for(int i = 0; i < dogs.size(); i++){
      if (bark >= dogs[i]){
        dogs[i] = bark + K;
        break;
      } else {
        dogs.push_back(bark + K);
      }
    }
  }
  cout << dogs.size() << endl;
}

When inputting the first test case the output is and should be '1'. But when running any other test case the it Exceeds the Memory Limit.

Answer 1

You end up with an infinite number of dogs as each dog you add in the for i loop fails the bark >= dogs[i] test which causes another dog to be added and so on.

Changing your code to only add one dog when no dogs match the condition works:

for (int bark : barks) {
    bool found = false;
    for (int i = 0; i < dogs.size(); i++) {
        if (bark >= dogs[i]) {
            dogs[i] = bark + K;
            found = true;
            break;
        }
    }
    if (!found)
    {
        dogs.push_back(bark + K);
    }
}

PS don't use #include <bits/stdc++.h> , it is non standard and only works on some platforms, include just the c++ headers you need (eg <iostream> and <vector> ) instead. using namespace std can also cause issues.