I have looked to no avail, and I'm 开发者_C百科afraid that it might be such a simple question that nobody dares ask it.
Can one input multiple things from standard input in one line? I mean this:
float a, b;
char c;
// It is safe to assume a, b, c will be in float, float, char form?
cin >> a >> b >> c;
Yes, you can input multiple items from cin
, using exactly the syntax you describe. The result is essentially identical to:
cin >> a;
cin >> b;
cin >> c;
This is due to a technique called "operator chaining".
Each call to operator>>(istream&, T)
(where T
is some arbitrary type) returns a reference to its first argument. So cin >> a
returns cin
, which can be used as (cin>>a)>>b
and so forth.
Note that each call to operator>>(istream&, T)
first consumes all whitespace characters, then as many characters as is required to satisfy the input operation, up to (but not including) the first next whitespace character, invalid character, or EOF.
Yes, you can.
From cplusplus.com:
Because these functions are operator overloading functions, the usual way in which they are called is:
strm >> variable;
Where
strm
is the identifier of a istream object andvariable
is an object of any type supported as right parameter. It is also possible to call a succession of extraction operations as:strm >> variable1 >> variable2 >> variable3; //...
which is the same as performing successive extractions from the same object
strm
.
Just replace strm
with cin
.
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