Computer Science I

Feb 15, 2006 - Problem: convert pounds to kilograms ... The weight-converter program reading from the keyboard and writing to ... foo.open("data_report.txt");.
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Computer Science I CS 135 3. File Input/Output a. Reading from the Keyboard b. Reading from an Input File c. Input & Output Streams 9 Streams are sequences of characters 9 Common streams: keyboard (cin) and screen (cout) 9 File streams: input files and output files

d. Writing to an Output File

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CS 135 - Computer Science I - 3. File Input/Output

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3.c Input & Output Streams Streams are sequences of characters

¾ Streams 9 a stream is a sequence of characters from a source to a destination

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an input stream is a sequence of characters from an input device or a file to a program in the computer

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an output stream is a sequence of characters from a program in the computer to an output device or a file

CS 135 - Computer Science I - 3. File Input/Output

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3.c Input & Output Streams Streams are sequences of characters

¾ Extraction operator >> and insertion operator > reads characters from an input stream and groups them into meaningful data –72.6 – 7 2 . 6 e w ...

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conversely, the insertion operator pounds;

// prompt user for weight in lbs cout > pounds;

// calculate weight in kilograms kilos = pounds / 2.2046;

// calculate weight in kilograms kilos = pounds / 2.2046;

// display result cout