1.
#include <iostream>
using namespace std;
int main()
{
int n;
cin >> n;
for (int i = n; i >= 1; --i)
{
if (i % 2 == 1)
{
cout << i << " ";
}
}
return 0;
}
2.
#include <iostream>
using namespace std;
int main()
{
int n, cnt = 0;
cin >> n;
while (n != 0)
{
cnt++;
n /= 10;
}
cout << cnt;
return 0;
}
3.
#include <iostream>
using namespace std;
int main()
{
int n, s = 0;
cin >> n;
while (n != 0)
{
int c = n % 10;
s += c;
n /= 10;
}
cout << s;
return 0;
}