Submission #798645

#	Time	Username	Problem	Language	Result	Execution time	Memory
798645		vjudge1	Palindrome-Free Numbers (BOI13_numbers)	C++17	100 / 100	1 ms	340 KiB

numbers

#include <bits/stdc++.h>
using namespace std;

#ifdef LOCAL
  #include "/home/trucmai/.vim/tools.h"
  #define debug(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;
  #else
  #define debug(x...)
#endif

void open(){
  if(fopen("i.inp","r")){
    freopen("i.inp","r",stdin);
    freopen("o.out","w",stdout);
  }
}

#define ll long long
#define all(a) (a).begin(), (a).end()
#define vi vector<ll>
#define pi pair<ll,ll>
#define pii pair<ll,pair<ll,ll>>
#define fi first
#define se second
#define gcd __gcd
#define mset(a,v) memset(a, v, sizeof(a))
#define endl '\n'
#define spc " "

const int MN1 = 1e6 + 5,MN2 = 1e4 + 5,LOG = 27;
const ll MOD = 1e9 + 7,INF = 1e9;
ll l,r,dp[20][11][11][2]; vi num;
ll f(ll i,ll d1,ll d2,bool tight){
  if(i == num.size()) return 1;
  ll &res = dp[i][d1+1][d2+1][tight]; 
  if(~res) return res; 
  res = 0; ll lim = (tight ? 9 : num[i]);
  for(ll digit = 0;digit <= lim;++digit){
    if(digit == d1 || digit == d2) continue;
    res += f(i+1,d2,((d2 == -1) && (digit == 0) ? -1 : digit),tight || (digit < lim));
  }
  return res;
}
ll calc(ll n){
  if(n <= 0) return (n == 0); 
  num.clear();
  while(n > 0) num.emplace_back(n % 10), n /= 10;
  reverse(all(num));
  mset(dp,-1);
  return f(0,-1,-1,false);
}
void solve(){
  cin>>l>>r;
  cout<<calc(r) - calc(l-1);
}

signed main(){
  cin.tie(0) -> sync_with_stdio(0);
  open();
  ll t = 1; //cin>>t;
  while(t--) solve(); 
  cerr << endl << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}

Compilation message (stderr)

numbers.cpp: In function 'long long int f(long long int, long long int, long long int, bool)':
numbers.cpp:34:8: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |   if(i == num.size()) return 1;
      |      ~~^~~~~~~~~~~~~
numbers.cpp: In function 'void open()':
numbers.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen("i.inp","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~
numbers.cpp:14:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |     freopen("o.out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~

• Subtask 1: 25 / 25
• Subtask 2: 75 / 75