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/* gator 2017
input: 1 5
output: 1
*/
#include <iostream>
#include <fstream>
bool pari(int n) { return ((n % 2) == 0) ? true : false; }
int sequenza(int n, bool pollatz, int tCollatz = -1)
{
int m, tot = 1;
if(pollatz)
m = 5;
else
m = 3;
while(n != 1) {
if(pari(n))
n /= 2;
else
n = n*m+1;
tot++;
if(tCollatz != -1 && tot > tCollatz)
break;
}
return tot;
}
int main()
{
std::ifstream in("input.txt");
std::ofstream out("output.txt");
int N1, N2, tot = 0, collatz;
in >> N1 >> N2;
for(int i = N1; i <= N2; i++) {
collatz = sequenza(i, false);
if(sequenza(i, true, collatz) < collatz)
tot++;
}
out << tot;
out.close();
in.close();
return 0;
}
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