Submission #462158

#	Time	Username	Problem	Language	Result	Execution time	Memory
462158		AlexLuchianov	PIN (CEOI10_pin)	C++14	30 / 100	27 ms	7864 KiB

pin

#include <iostream>
#include <vector>
#include <algorithm>

using ll = long long;

int const sigma = 37;
int const nmax = sigma * sigma * sigma * sigma;
int frec[sigma][sigma][sigma][sigma];
ll dp[1 + 4];

int convert(char ch) {
  if('0' <= ch && ch <= '9')
    return ch - '0' + 1;
  else
    return ch - 'a' + 11;
}

int main() {
  int n, target;
  std::cin >> n >> target;
  for(int i = 1;i <= n; i++) {
    std::string s;
    std::cin >> s;
    int a = convert(s[0]), b = convert(s[1]), c = convert(s[2]), d = convert(s[3]);
    for(int mask = 0; mask < (1 << 4); mask++) {
      frec[a * (0 < (mask & (1 << 3)))][b * (0 < (mask & (1 << 2)))][c * (0 < (mask & (1 << 1)))][d * (0 < (mask & (1 << 0)))]++;
    }
  }
  for(int a = 0; a < sigma; a++)
    for(int b = 0; b < sigma; b++)
      for(int c = 0; c < sigma; c++)
        for(int d = 0; d < sigma; d++)
          dp[(a == 0) + (b == 0) + (c == 0) + (d == 0)] += 1LL * frec[a][b][c][d] * (frec[a][b][c][d] - 1) / 2;
  
  for(int i = 1; i <= target; i++)
    for(int j = 1; j < i; j++)
      dp[i] -= dp[j];
  std::cout << dp[target];
  return 0;
}

• Subtask 1: 30 / 100