Submission #1120449

#	Time	Username	Problem	Language	Result	Execution time	Memory
1120449		HasanV11010238	Palindrome-Free Numbers (BOI13_numbers)	C++17	77.50 / 100	2 ms	580 KiB

numbers

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long long
#define INF 1000000000
ll calc(string a, string b){
    while (a.size() < b.size()){
        a = "0" + a;
    }
    int n = b.size();
    vector<vector<vector<vector<ll>>>> dp(n + 1, vector<vector<vector<ll>>>(10, vector<vector<ll>>(10, vector<ll>(4, 0))));
    if (a[0] == b[0]){
        dp[0][a[0] - '0'][a[0] - '0'][3] = 1;
    }
    else{
        int st = a[0] - '0', en = b[0] - '0';
        for (int i = st + 1; i < en; i++){
            dp[0][i][i][0] = 1;
        }
        dp[0][st][st][1] = dp[0][en][en][2] = 1;
    }
    for (int i = 1; i < n; i++){
        int st = a[i] - '0', en = b[i] - '0';
        for (int j = 0; j < 10; j++){
            for (int k = 0; k < 10; k++){
                for (int l = 0; l < 4; l++){
                    for (int no = 0; no < 10; no++){
                        if (no == j || no == k) continue;
                        if (no < st && (l == 1 || l == 3)) continue;
                        if (no > en && (l == 2 || l == 3)) continue;
                        int ne = 0;
                        if (no == st && (l == 1 || l == 3)){
                            ne += 1;
                        }
                        if (no == en && (l == 2 || l == 3)){
                            ne += 2;
                        }
                        dp[i][k][no][ne] += dp[i - 1][j][k][l];
                    }
                }
            }
        }
    }
    ll ans = 0;
    for (int i = 0; i < 10; i++){
        for (int j = 0; j < 10; j++){
            for (int k = 0; k < 4; k++){
                ans += dp[n - 1][i][j][k];
            }
        }
    }
    return ans;
}
int main(){
    unsigned ll a, b, ans = 0;
    cin>>a>>b;
    string str1 = "0", str2 = "9";
    for (int i = 0; i < 20; i++){
        unsigned ll nu1 = stoull(str1), nu2 = stoull(str2);
        if (nu1 > b){
            break;
        }
        if (nu2 < a){
            str1 = "1" + str1, str2 = str2 + "9";
            continue;
        }
        ans += calc(to_string(max(nu1, a)), to_string(min(nu2, b)));
        str1 = "1" + str1, str2 = str2 + "9";
    }
    cout<<ans;
}

• Subtask 1: 17.5 / 25
• Subtask 2: 60 / 75