What is implicit conversion in C++ ?

Question

What type of conversion is not accepted in C and why?
a) char to int
b) float to char pointer
c) int to char
d) double to char

Answer 1

Implicit conversions are automatically performed when a value is copied to a compatible type. For example:

short a=2000;
int b;
b=a;

the value of a is promoted from short to int without the need of any explicit operator. This is known as a standard conversion. Standard conversions affect fundamental data types, and allow the conversions between numerical types (short to int, int to float, double to int...), to or from bool, and some pointer conversions.
go through this link for more details: http://www.cplusplus.com/doc/tutorial/typecasting/