UVa 11678 - Cards' Exchange

Accepted date: 2013-12-03
Ranking (as of 2013-12-03): 66 out of 606
Language: C++

/*
  UVa 11678 - Cards' Exchange

  To build using Visual Studio 2012:
    cl -EHsc -O2 UVa_11678_Cards_Exchange.cpp
*/

#include <algorithm>
#include <cstdio>
using namespace std;

const int nr_cards_max = 10000;
int alice_cards[nr_cards_max], betty_cards[nr_cards_max];

int skip_cards(int nc, int ic, const int cards[])
{
  int c = cards[ic++];
  for ( ; ic < nc; ic++)
    if (cards[ic] != c)
        break;
  return ic;
}

int main()
{
  while (true) {
    int na, nb;
    scanf("%d %d", &na, &nb);
    if (!na & !nb)
      break;
    for (int i = 0; i < na; i++)
      scanf("%d", &alice_cards[i]);
    for (int i = 0; i < nb; i++)
      scanf("%d", &betty_cards[i]);
    int xa = 0, xb = 0;
    for (int ia = 0, ib = 0; ia < na || ib < nb; ) {
      if (ia < na && ib < nb) {
        if (alice_cards[ia] < betty_cards[ib]) {
          xa++;
          ia = skip_cards(na, ia, alice_cards);
        }
        else if (alice_cards[ia] > betty_cards[ib]) {
          xb++;
          ib = skip_cards(nb, ib, betty_cards);
        }
        else {
          ia = skip_cards(na, ia, alice_cards);
          ib = skip_cards(nb, ib, betty_cards);
        }
      }
      else if (ia < na) {
        xa++;
        ia = skip_cards(na, ia, alice_cards);
      }
      else {
        xb++;
        ib = skip_cards(nb, ib, betty_cards);
      }
    }
    printf("%d\n", min(xa, xb));
  }
  return 0;
}