How to set limit in while loop. Eg.while (20<num<30)?

Question

#include <iostream>
using namespace std;

int main()
{
int num;
cin>>num;
while(10<num<20) {
cout<<"number:"<<num<<endl;
num++;
}
return 0;
} I've tried this code but whenever I put any number output is showing unlimited numbers..?

Answer 1

You must use a composite boolean operation: instead of
10<num<20
try
num>10 && num<20