Wha ... this is getting boring.
Statutory Warning: Spoilers ahead
using std::vector;
static const int kMaxNumbers = 1000000;
bool isPalindromic(int n, int base) {
vector<int> digits;
while (n > 0) {
digits.push_back(n % base);
n /= base;
}
int length = digits.size();
for (int i = 0; i < length/2; ++i) {
if (digits[i] != digits[length-1-i]) {
return false;
}
}
return true;
}
int main() {
int sum = 0;
for (int i = 1; i < kMaxNumbers; ++i) {
if (isPalindromic(i, 10) && isPalindromic(i, 2)) {
sum += i;
}
}
std::cout << "Sum of palindromic numbers = " << sum << std::endl;
}
(runs in 931 milliseconds)