How can I make this code any faster? Right now it is exceeding the time limit of 2 seconds.
Help would be greatly appreciated.
Here’s the question: http://www.codechef.com/problems/SDSQUARE
#include <iostream>
#include <math.h>
using namespace std;
bool check(int num){ // Check if number is consisted of all squares
int temp;
while (num > 0){
temp = num % 10;
if (temp != 0 && temp != 1 && temp != 4 && temp != 9){
return false;
}
num /= 10;
}
return true;
}
int main() {
int t, a, b, i;
cin >> t;
while (t--){
i = 0;
cin >> a >> b;
int l = floor(sqrt(a));
int r = pow(l, 2);
while (r <= b){
if (check(r) == true){ // Check if square is made of "perfect digits"
i++; // Increment the count of perfect digit squares
}
r += 2 * l + 1; // Find next square
l++; // Increment the square root
}
cout << i << endl;
}
}
