Logical functions
We have discussed the If, 'While and For' Statements, and have used expressions within our syntax i.e.
If ( expression)
Statement 1;
else
Statement 2;
do
statement;
while (expression);
for (init;expression;alter)
statement;
while ( expression)
statement;
We tended to restrict ourselves to simple expression i.e A == 5 etc. This is a simplification of what an expression really is. The equality sign indicates a logical identity i.e. true or false. Many other logical expressions could yield true or false .The most common ones are AND '&&', OR '||' and NOT '!' , these behave identical to there truth table counterparts . Therefore a valid expression could be
(age > 40) &&( term < 10)
If age is greater than 40 and term is less than 10 then it is true or false
(age > 40) || (term <10)
If age is greater than 40 or term is less than 10 then it is true or false
(age !> 40) || (term <10)
If age is not greater than 40 or term is less than 10 then it is true or false