Java class

Outline for loop while loop do while loop How to choose? Nested loop

for loop EX: for ( i=0 ; i<=100 ; i++ ) // 迴圈條件運算式 { // 迴圈內的動作 ; }

迴圈內的動作 進入迴圈 true false 離開迴圈 迴圈條件運算式

while loop EX: int count=0; while ( count<100 ) { System.out.println(”Hello!”); count++; } p.s count 從 0 累加到 99

loop- continuation condition? Statement(s) (loop body) false true count=0 (count < 100) ? System.out.println(“Hello!”); count++;

練習 : 用 for loop 以及 while loop, 寫九九乘法表 格式 :

do while loop EX: int count=0; do { System.out.println(”Hello!”); count++; } while ( count<100 );

loop- continuation condition? Statement(s) (loop body) false true count=0 (count < 100) ? System.out.println(“Hello!”); count++;

Pretest & Posttest loop 先測迴圈 : while 、 for The condition is checked before the loop body is excuted. 後測迴圈 : do while The condition is checked after the loop body is excuted.

How to choose? A for loop may be used if the number of repetitions is known in advance. A while loop may be used if the number of repetitions is not fixed. A do while loop can be used to replace a while loop if the loop body has to be executed before the condition is tested. 課本 p.152

Nested( 巢狀 ) loop for { ……. for { ……. } 課本 p.153

回家看 : p.152 ~ p.153