#include <bits/stdc++.h>
using namespace std;
bool isPalindrome (int64_t i) {
string s = to_string(i);
bool fine = true;
for (int j = 0; j < s.length(); j++) {
if (j >= 1 && s[j] == s[j - 1]) {
fine = false;
}
if (j >= 2 && s[j] == s[j - 2]) {
fine = false;
}
}
return fine;
}
int64_t powerOf10 (int x) {
//pow(10, x)
if (x == 1) {
return 10;
}
int64_t tot = 81;
for (int i = 0; i < x - 2; i++) {
tot *= 8;
}
return tot + powerOf10(x - 1);
}
int64_t res (int64_t a, int64_t b) {
int64_t ans = 0;
for (int64_t i = a; i <= b; i++) {
ans += isPalindrome(i);
}
return ans;
}
int64_t removeAllBut2 (int64_t x) {
string s = to_string(x);
for (int i = 2; i < s.length(); i++) {
s[i] = '0';
}
return stoll(s);
}
int64_t query (int64_t a, int64_t b) {
if (b - a <= 1000) {
return res(a, b);
}
if (a != 0) {
return query(0, b) - query(0, a - 1);
}
if (a == b) {
return a;
}
string s = to_string(b);
int64_t tot = 0;
int64_t c = 0;
for (int i = 1; i <= 9; i++) {
for (int j = 0; j <= 9; j++) {
for (int k = 0; k <= 9; k++) {
if (i == j || j == k || i == k) continue;
c += (100 * i + 10 * j + k < 100 * (s[0] - '0') + 10 * (s[1] - '0') + (s[2] - '0'));
if (i == s[0] - '0' && j == s[1] - '0' && k == s[2] - '0') {
char ch = s.front();
reverse(s.begin(), s.end());
s.pop_back();
reverse(s.begin(), s.end());
tot += query(removeAllBut2(stoll(s)), stoll(s));;
s = ch + s;
}
}
}
}
tot += powerOf10((int)s.length() - 1);
int t = s.size() - 3;
while (t--) {
c *= 8;
}
return tot + c;0
}
int main() {
int64_t a, b;
cin >> a >> b;
cout << query(a, b) << '\n';
}
Compilation message
numbers.cpp: In function 'bool isPalindrome(int64_t)':
numbers.cpp:6:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
6 | for (int j = 0; j < s.length(); j++) {
| ~~^~~~~~~~~~~~
numbers.cpp: In function 'int64_t removeAllBut2(int64_t)':
numbers.cpp:36:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
36 | for (int i = 2; i < s.length(); i++) {
| ~~^~~~~~~~~~~~
numbers.cpp: In function 'int64_t query(int64_t, int64_t)':
numbers.cpp:75:21: error: expected ';' before '}' token
75 | return tot + c;0
| ^
| ;
76 | }
| ~
numbers.cpp:75:20: warning: statement has no effect [-Wunused-value]
75 | return tot + c;0
| ^
