3 3 Side Effects A side effect is

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3 -3 Side Effects A side effect is an action that results from evaluation

3 -3 Side Effects A side effect is an action that results from evaluation of an expression. For example, in assignment, C first evaluates the expression on right of the assignment operator and then places value in the left variable. Changing the value of left variable is a side effect. Computer Science: A Structured Programming Approach Using C 1 the an the the

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 2

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 2

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 3

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 3

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 4

PROGRAM 3 -6 Evaluating Expressions Computer Science: A Structured Programming Approach Using C 4

Warning Computer Science: A Structured Programming Approach Using C 5

Warning Computer Science: A Structured Programming Approach Using C 5

3 -5 Type Conversion Up to this point, we have assumed that all of

3 -5 Type Conversion Up to this point, we have assumed that all of our expressions involved data of the same type. But, what happens when we write an expression that involves two different data types, such as multiplying an integer and a floating-point number? To perform these evaluations, one of the types must be converted. Topics discussed in this section: Implicit Type Conversion Explicit Type Conversion (Cast) Computer Science: A Structured Programming Approach Using C 6

FIGURE 3 -10 Conversion Rank Computer Science: A Structured Programming Approach Using C 7

FIGURE 3 -10 Conversion Rank Computer Science: A Structured Programming Approach Using C 7

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C 8

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C 9

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C

PROGRAM 3 -7 Implicit Type Conversion Computer Science: A Structured Programming Approach Using C 10

Implicit Conversion of Ints and Floats int i = 3; float f = 2.

Implicit Conversion of Ints and Floats int i = 3; float f = 2. 5; i = f; // i will equal 2 after this f = 3/i; // f will equal 1. 0 after this f = i + 0. 6; // f will equal 2. 6 after this i = 2. 0 * 2. 4; // i will equal 4 after this Computer Science: A Structured Programming Approach Using C 11

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 12

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 12

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 13

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 13

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 14

PROGRAM 3 -8 Explicit Casts Computer Science: A Structured Programming Approach Using C 14

3 -6 Statements A statement causes an action to be performed by the program.

3 -6 Statements A statement causes an action to be performed by the program. It translates directly into one or more executable computer instructions. You may have noticed that we have used a semicolon at the end of the statements in our programs. Most statements need a semicolon at the end; some do not. Computer Science: A Structured Programming Approach Using C 15

FIGURE 3 -12 Compound Statement Computer Science: A Structured Programming Approach Using C 16

FIGURE 3 -12 Compound Statement Computer Science: A Structured Programming Approach Using C 16