why there is any need for cout.put()?

why there is any need for cout.put()?

much of  the answer is historical.Before release 2.0 of c++ .cout would display character variables as characrers but display character constans.such as 'M' and 'N' as numbers.the problem was that earlier versions of c++，like C stored character constans as int .That is , the 

the code 77 for 'M' would be stored in a 16-bit or 32-bit unit .meanwhile char variables typically occupied 8 bits a statement like the following copied 8 bits (the important 8 ) from the constant 'M' to the varable ch .

char ch = 'M'

unfortunates this mean that.to cout 'M' and ch looked quite different from one another.even though both held the same value.so a statement like the following wolud print the $ character rather than the simple display $

cout<<'$'

but the following would print the character as designed cout.put('$');

now after release 2.0 c++ stores single character constants as type char not type int therefore cout now correctly handles characters constants.

summary:

with the english c++ book we can know many what we want to know , and that is very useful knowledge.study c++ and computer with english is coor.