The counter declaration and initialization clause
(Display Figure 6.)
The counter declaration and initialization clause is executed once and only once when control first enters the for loop structure.
After that clause is executed, control passes to the conditional clause.
The purpose of this clause is to initialize the value of the counter variable named index to zero.
Once index is declared and initialized to a value of 0, this clause is never executed again (unless control leaves the loop and later returns to the same section of code).