Submission #492930

#	Time	Username	Problem	Language	Result	Execution time	Memory
492930		SlavicG	Lucky Numbers (RMI19_lucky)	C++17	28 / 100	1 ms	460 KiB

lucky

#include "bits/stdc++.h"
using namespace std;
 
#define ll long long
 
#define       forn(i,n)              for(int i=0;i<n;i++)
#define          all(v)              v.begin(), v.end()
#define         rall(v)              v.rbegin(),v.rend()
 
#define            pb                push_back
#define          sz(a)               (int)a.size()
 
const int N = 30, mod = 1e9 + 7;
ll dp[N][10][2];
 
#define int long long
ll calc(string s){
    if(s == "0")return 1;
    int n = sz(s);
    forn(i, N)forn(j, 10)forn(k, 2)dp[i][j][k] = 0;
    for(int d = 1;d <= s[0] - '0'; ++d){
        dp[0][d][(int)(d < (s[0] - '0'))] = 1;
    }   
    for(int i = 1;i < n; ++i){
        for(int lst = 0; lst <= 9; ++lst){
            for(int cur = 0;cur <= 9; ++cur){
                if(lst == 1 && cur == 3)continue;
                if(cur < (s[i] - '0')){
                    dp[i][cur][1] += (dp[i - 1][lst][0] + dp[i - 1][lst][1]) % mod;
                    dp[i][cur][1] %= mod;
 
                }else if(cur == (s[i] - '0')){
                    dp[i][cur][1] += dp[i - 1][lst][1];
                    dp[i][cur][1] %= mod;
 
                    dp[i][cur][0] += dp[i - 1][lst][0];
                    dp[i][cur][0] %= mod; 
                }else{
                    dp[i][cur][1] += dp[i - 1][lst][1];
                    dp[i][cur][1] %= mod;
                }
            }
        }
    }
 
    int ans = 0;
    for(int i = 0;i <= 9; ++i){
        ans += (dp[n - 1][i][0] + dp[n - 1][i][1]) % mod;
        ans %= mod;
    }
    return ans;
}
 
ll cnt(string s){
    if(s.empty())return 0;
    if(s == "0")return 1;
    ll ans = calc(s);
 
    string a = "9";
    while(sz(a) < sz(s)){
        ans += calc(a);
        ans %= mod;
        a += '9';
    }
 
    return (ans + 1) % mod;
}
 
void solve()
{
    int n, q;
    string s;
    cin >> n >> q >> s;
    assert(q == 0);

    while(s[0] == '0')s.erase(s.begin());
    cout << cnt(s) % mod << "\n";
}   
 
int32_t main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int t = 1;
    //cin >> t;
    while(t--)
    {
        solve();
    }
}

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 27
• Subtask 5: 0 / 9
• Subtask 6: 0 / 27