The C ++ program has a small problem (input stream)

# Include <iostream>
Int main ()
{
Char ch;
STD: CIN> CH;
While (Ch! = 'Q ')
{
Int sum = 0, value;
While (STD: CIN> value)
Sum + = value;
STD: cout <"sum is:" <sum <STD: Endl;

STD: cout <"Please input ch" <STD: Endl;

STD: CIN> CH;
}
Return 0;

}

After I run it, I enter a character and a number to sum the values, but the subsequent programs cannot control it;

Where is the problem?

If you want the while (STD: CIN> value) condition to be false, you must enter an invalid character;

This value remains in the input stream after it is input, and the status bit is set, and the input is closed.

Therefore

Add STD: CIN before STD: CIN> CH. clear (); // clear the status bit STD: cin. ignore (); // read and discard a character. STD: CIN> CH;