vector_vs_pair.cpp

#include <bits/stdc++.h>
using namespace std;
using VI = vector<int>;
using PII = pair<int, int>;
using ull = unsigned long long;

#define trace(v) cerr << ">> " << #v << " = " << v << "\n"

int N;

void test_vector() {
  cerr << "TESTING VECTOR\n";
  VI init = {0, 0};
  vector<VI> v(N, init);
  int *p1 = &(v[0][0]);
  int *p2 = &(v[1][0]);
  int *p3 = &(v[2][0]);
  trace((p2 - p1));
  trace((p3 - p2));
}
void test_pair() {
  cerr << "TESTING PAIR\n";
  PII init = {0, 0};
  vector<PII> v(N, init);
  int *p1 = &(v[0].first);
  int *p2 = &(v[1].first);
  int *p3 = &(v[2].first);
  trace((p2 - p1));
  trace((p3 - p2));
}

int main() {
  cin >> N;
  test_vector();
  test_pair();
  return 0;
}