Designing I/O
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Immediately before cin is used to input data from the keyboard,
the program should always prompt the user to enter the proper data. For example,
cout << "Enter the number of candy bars in a package\n";
cout << "and the weight in ounces of one candy bar.\n";
cout << "Then press return\n";
cin >> number_of_bars;
cin >> one_weight;
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Should always end the program with endl or \n.
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\n is an example of an escape sequence. It is a single non-printable character. Another useful escape sequence is \t,
which represents a horizontal tab (usually 8 spaces).
In general the backslash \ tells the compiler to interpret the next character differently.
Other escape sequences are:
\a alert
\\ a single backslash
\" a double quote
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Formatting numbers with a decimal point for output
- The output stream cout has member functions that
allows one to control the output format of numbers with decimal points (floats and doubles)
- Example:
Using the code:
cout.setf(ios::fixed); // always uses fixed point rather than scientific notation
cout.setf(ios::showpoint); // always shows a decimal point
cout.precision(5); // shows exactly 5 decimal places with rounding;
//the output of a number such as 3.14159625358979 will appear as 3.14160