1.5. Expressions
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Lecturer: PhD. DO Thi Ngoc Diep
SCHOOL OF ELECTRICAL AND ELECTRONIC ENGINEERING
HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY
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Expression
•An expression that contains at least one operand and 0 or more operators
•The operands can be: constant values, literals, variables, result of a function or
subexpressions
•Operators have different precedence, but can be changed using brackets ()
•Operators with the same precedence are performed from left to right
•Examples:
•47
•i
•x++
•sin(x+2)
•( 2 * log( ( 3 + 10 ) - ( 2 * 6 ) ) )
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1.6. Operators
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Operators in C
•Assignment operator (=, +=, -=, *=, /=, …)
•Arithmetic operators ( +, -, *, /, %)
•Relational / comparison operators (==, != , >, <, >= , <=)
•Bit operators (&, |, ^, ~, <<, >>)
•Logical operators (&&, ||, !)
•Other operators (sizeof(), pointer: *, address: &, etc.)
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Assignment operator
•=, +=, -=, *=, /=, %=
•=
•+=, -=, *=, /= , %=, &=, |=, ^=, >>=, <<=
a -= 5; means a = a - 5;
a /= b; means a = a / b;
•a = b = c = 1 ;
•int i=2, j, k ;
k=(j=i , i*2); /* j=i; k=i*2 ;
Result: i=2;j=2;k=4 */