indexingvsat.cpp

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//: C20:IndexingVsAt.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Comparing "at()" to operator[]
#include "../require.h"
#include <vector>
#include <deque>
#include <iostream>
#include <ctime>
using namespace std;

int main(int argc, char* argv[]) {
  requireMinArgs(argc, 1);
  long count = 1000;
  int sz = 1000;
  if(argc >= 2) count = atoi(argv[1]);
  if(argc >= 3) sz = atoi(argv[2]);
  vector<int> vi(sz);
  clock_t ticks = clock();
  for(int i1 = 0; i1 < count; i1++)
    for(int j = 0; j < sz; j++)
      vi[j];
  cout << "vector[]" << clock() - ticks << endl;
  ticks = clock();
  for(int i2 = 0; i2 < count; i2++)
    for(int j = 0; j < sz; j++)
      vi.at(j);
  cout << "vector::at()" << clock()-ticks <<endl;
  deque<int> di(sz);
  ticks = clock();
  for(int i3 = 0; i3 < count; i3++)
    for(int j = 0; j < sz; j++)
      di[j];
  cout << "deque[]" << clock() - ticks << endl;
  ticks = clock();
  for(int i4 = 0; i4 < count; i4++)
    for(int j = 0; j < sz; j++)
      di.at(j);
  cout << "deque::at()" << clock()-ticks <<endl;
  // Demonstrate at() when you go out of bounds:
  di.at(vi.size() + 1);
} ///:~