Submission #894614

#	Time	Username	Problem	Language	Result	Execution time	Memory
894614		IWKR	Palindrome-Free Numbers (BOI13_numbers)	C++17	100 / 100	2 ms	604 KiB

numbers

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

#define int long long

int dp[20][10][10][2][2][2];

int cal(int len, int l, int ll, bool bound, bool zero1, bool zero2, string target) {
    if (len == target.size()) {
        return 1;
    }
    if (dp[len][l][ll][bound][zero1][zero2] != -1) {
        return dp[len][l][ll][bound][zero1][zero2];
    }
    int ans = 0;
    for (int i = 0; i <= 9; i++) {
        if ((!zero1 && i == l) || (!zero2 && i == ll)) {
            continue;
        } else {
            if (bound && i > target[len] - '0') {
                break;
            }
            ans += cal(len + 1, i, l, bound && (i == target[len] - '0'), i == 0 && zero1, zero1, target);
        }
    }
    dp[len][l][ll][bound][zero1][zero2] = ans;
    return ans;
}

int32_t main() {
    int a, b;
    cin >> a >> b;
    string s = to_string(a - 1);
    string t = to_string(b);
    memset(dp, -1, sizeof dp);
    int ans = cal(0, 0, 0, true, true, true, t);
    memset(dp, -1, sizeof dp);
    cout << ans - cal(0, 0, 0, true, true, true, s);
}

Compilation message (stderr)

numbers.cpp: In function 'long long int cal(long long int, long long int, long long int, bool, bool, bool, std::string)':
numbers.cpp:9:13: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |     if (len == target.size()) {
      |         ~~~~^~~~~~~~~~~~~~~~

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