Write a program in C, get the current system of shaping digital long (16-bit, 32-bit, 64-bit), etc., can not use sizeof ()

#include <iostream>
#include <cmath>
using namespace Std;

int main ()
{
int num =-1;
unsigned int s = num; The current bit-level representation is the maximum number of unsigned
cout << (int) log2 (s) +1 << Endl; First Kind

int intSize = 0;
while (s! = 0)
{
s = S >> 1;
IntSize = intSize + 1;
}
cout << intSize << Endl; Loop processing also OK

int n = 1; Directly with 1, shifted, until 0
int cn = 0;
while (n!=0)
{
n = (n << 1);
cn++;
}
cout << cn<< Endl;
return 0;
}

Write a program in C, get the current system of shaping digital long (16-bit, 32-bit, 64-bit), etc., can not use sizeof ()