Function Overloading - Ambiguity

Ambiguity in function overloading arises when

1) Function 1 takes in char, Function 2 takes in int

   Function call sends a float/double/long

2) Function 1 takes in char, Function 2 takes in float
   Function call sends a double/int/long

3) Function 1 takes in int and a default integer value, Function 2 takes in integer,
   Function call sends an int/float/double

Example 1

#include <iostream.h>
void fun(char  x)
{
cout<<x;
}
void fun(int ch)
{
cout<<ch;
}
void main()
{
fun(10.5f);
}

Example 2
#include <iostream.h>
void fun(char  x)
{
cout<<x;
}
void fun(float ch)
{
cout<<ch;
}
void main()
{
fun(10.5);

}

Example 3
#include <iostream.h>
void fun(int x, int y=5)
{
cout<<x;
}
void fun(int ch)
{
cout<<ch;
}
void main()
{
fun(10);

}