Submission #1077286

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077286		steveonalex	Palindrome-Free Numbers (BOI13_numbers)	C++17	100 / 100	1 ms	468 KiB

numbers

// #include "aliens.h"
#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
#define block_of_code if(true)
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll lcm(ll a, ll b){return a / gcd(a, b) * b;}
 
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}
 
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
double rngesus_d(double l, double r){
    double cur = rngesus(0, MASK(60) - 1);
    cur /= MASK(60) - 1;
    return l + cur * (r - l);
}
 
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }
 
template <class T>
    void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
        for(auto item: container) out << item << separator;
        out << finish;
    }
 
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

const int N = 19;
ll dp[N][11][11][2][2];

ll go(string &s, int digit, int last1, int last2, int isEmpty, int flag){
    if (digit == s.size()){
        return 1;
    }
    if (dp[digit][last1][last2][isEmpty][flag] != -1) return dp[digit][last1][last2][isEmpty][flag];
    int r = 9;
    if (flag) r = s[digit] - '0';
    ll ans = 0;
    for(int i = 0; i<=r; ++i){
        int _flag = flag && (i == r);
        if (isEmpty && i == 0) ans += go(s, digit + 1, 10, 10, 1, _flag);
        else if (i != last1 && i != last2) ans += go(s, digit + 1, i, last1, false, _flag);
    }
    return dp[digit][last1][last2][isEmpty][flag] = ans;
}

ll dpdp(ll x){
    memset(dp, -1, sizeof dp);
    string s = to_string(x);

    return go(s, 0, 10, 10, 1, 1);
}

int main(void){
    ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
    clock_t start = clock();

    ll a, b; cin >> a >> b;
    ll ans = dpdp(b);
    if (a > 0) ans -= dpdp(a - 1);

    cout << ans << "\n";
 
    cerr << "Time elapsed: " << clock() - start << " ms\n";
    return 0;
}

Compilation message (stderr)

numbers.cpp: In function 'll go(std::string&, int, int, int, int, int)':
numbers.cpp:60:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |     if (digit == s.size()){
      |         ~~~~~~^~~~~~~~~~~

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