Question

COBOL中的循环语句词有哪些？

Answer 1

PERFORM 过程名1 [THROUGH/THRU] 过程名2
[VARYING 参数1 FROM 初值1 BY 步长1 UNTIL 条件1]
[AFTER 参数2 FROM 初值2 BY 步长2 UNTIL 条件2]
[AFTER 参数3 FROM 初值3 BY 步长3 UNTIL 条件3]
END-PERFORM.

还有一个
IF ~
ELSE ~
END-IF.

Answer 2

PERFORM UNTIL 条件
过程
END-PERFORM

PERFORM 过程 UNTIL 条件
END-PERFORM

IF 条件 THEN
GO TO 本节首
ELSE
EXIT SECSION
END-IF

Answer 3

PERFORM FROM 1 VARYING 1 UNTIL 条件
...
END-PERFORM

Answer 4

fetch;if....else

Answer 5

PERFORM .... n TIMES
PERFORM ... UNTIL ...
PERFORM ... VARYING...