55 lines
1.7 KiB
C++
55 lines
1.7 KiB
C++
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// DataTypes 1, program 1: DataTypes1_01.cpp
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//
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#include <iostream>
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#include <string>
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#include <cctype> // required for chharacter functions
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using namespace std;
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// This program looks at char variables and how they correspond
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// to integers.
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//
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int main()
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{
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const float PI = 3.14159;
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int count; // loop control variable
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char letter; // holds character corresponding to count
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string line; // used for program flow control
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// can you assign a character variable to a string
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letter='j';
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line = letter;
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cout << "Assigned character variable to a string variable: " << line << endl;
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// print out the corresponding character for an integer value
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// The machine has the ascii character set, so only integers
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// 0 to 127 have significance. However, there are other
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// characters available for values 128 to 255. Note that since
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// char variables are only one byte, the highest integer value
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// that can be assigned to them is 255. A value of 256 results
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// in a wrapping back to 0, 257 to 1, etc.
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for (count = 0 ; count < 260; count++)
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{
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letter = count; // use implicit coercion to assign an integer value
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// to the char variable letter
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cout << "Count: " << count;
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cout << " integer(0-256): " << count%256 << " is: " << letter << endl;
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// put a pause in the printing of the values after every 20 values.
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// Note testing for a vlue of 19 instead of 0 since count starts at 0
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// if I tested for equal to 0, I would get a pause after one value and then every
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// twenty. by testing on 19, the first pause occurs after 20 values every time
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if (count%20 == 19)
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{
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cout << "press enter to continue:";
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getline(cin,line);
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}
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}
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return 0;
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}
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