DIY Moving Message Display

LED_DATA = (ledArray[i] & row) ? 1 : 0;

if (ledArray[i] & row)
   LED_DATA = 1;
else
   LED_DATA = 0;

`C++ How to Program´ said:

Code:

if ( grade >= 60 )
   cout << "Passed";
else
   cout << "Failed";

...
C++ provides the conditional operator (?:) that is closely related to the if/else structure. The conditional operator is C++'s only tenary operator - it takes three operands. The operands, together with the conditional operator, form a conditional expression. The first operand is a condition, the second operand is the value for the entire conditional expression if the condition is true and the third operand is the value for the entire conditional expression if the condition is false. For example, the output statement

Code:

grade >= 60 ? cout << "Passed" : cout << "Failed";

contains a conditional expression that evaluates to the string "Passed" if the condition grade >= 60 is true and evaluates to the string "Failed" if the condition is false. Thus, the statement with the conditional operator performs essentially the same as the preceding if/else statement. As we will see, the precedence of the conditional operator is low, so the parentheses in the preceding expression is required.
The values in a conditional expression can also be actions to execute. For example, the conditional expression

Code:

cout << ( grade >= 60 ? "Passed" : "Failed" );

is read, `If grade is greater than that or equal to 60, then cout << "Passed"; otherwise cout << "Failed".´ This too, is comparable to the preceding if/else structure. We will see that conditional operators can be used in some situations wheres is/else statements cannot.

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