Cod sursa(job #1096262)

Utilizator andrei.sfrentSfrent Andrei andrei.sfrent Data 1 februarie 2014 19:31:05
Problema Lista lui Andrei Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.01 kb
#include <fstream>

using namespace std;

#define MOD 104659

ifstream fi("nrcuv.in");
ofstream fo("nrcuv.out");

int N, M;
bool perm[256][256];

void init_perm() {
  for(int i = 0; i < 256; ++i) {
    for(int j = 0; j < 256; ++j) {
      perm[i][j] = true;
    }
  }
}

void read() {
  fi >> N >> M;
  for(int i = 0; i < M; ++i) {
    char x, y;
    fi >> x >> y;
    perm[(int)x][(int)y] = perm[(int)y][(int)x] = false;
  }
}

int mem[1001][256];

void init_mem() {
  for(int i = 0; i < 1001; ++i)
    for(int j = 0; j < 256; ++j)
      mem[i][j] = -1;
}

int f(int N, int s) {
  // cate numere de N incep cu s.
  if(N == 1) return 1;
  if(mem[N][s] == -1) {
    int sum = 0;
    for(int i = 'a'; i <= 'z'; ++i) {
      if(perm[s][i]) {
        sum += f(N - 1, i);
      }
    }
    mem[N][s] = sum % MOD;
  }
  return mem[N][s];
}

int main(int argc, char *argv[]) {
  init_perm();
  read();
  init_mem();

  int sum = 0;
  for(int i = 'a'; i <= 'z'; ++i) sum += f(N, i);
  sum = sum % MOD;

  fo << sum << endl;

  return 0;
}