#include <bits/stdc++.h>
using namespace std;
bool isPalindrome(const string &str) {
string s1 = str.substr(0, str.size() / 2 + str.size() % 2);
string s2 = str.substr(str.size() / 2);
ranges::reverse(s2);
return s1 == s2;
}
template <typename func> bool forAll(const string &str, const func &f) {
for (size_t i = 0; i < str.size(); i++) {
for (size_t j = 2; j <= str.size() - i; j++) {
string substr = str.substr(i, j);
if (f(substr)) {
return false;
}
}
}
return true;
}
int main() {
int a, b, ans = 0;
cin >> a >> b;
for (int i = a; i <= b; i++) {
string str = to_string(i);
if (forAll(str, isPalindrome)) {
ans++;
}
}
cout << ans << '\n';
}
Compilation message
numbers.cpp: In function 'bool isPalindrome(const string&)':
numbers.cpp:7:3: error: 'ranges' has not been declared
7 | ranges::reverse(s2);
| ^~~~~~
