📅  最后修改于: 2020-11-04 06:14:18             🧑  作者: Mango
决策结构要求程序员确定一个或多个要由程序评估或测试的条件,以及要确定的条件为真的情况下要执行的一条或多条语句,以及可选地,如果条件为真,则要指定其他要执行的语句条件确定为假。
以下是大多数编程语言中常见的典型决策结构的一般形式-
Fortran提供以下类型的决策构造。
Sr.No | Statement & Description |
---|---|
1 | If… then construct
An if… then… end if statement consists of a logical expression followed by one or more statements. |
2 | If… then…else construct
An if… then statement can be followed by an optional else statement, which executes when the logical expression is false. |
3 | if…else if…else Statement
An if statement construct can have one or more optional else-if constructs. When the if condition fails, the immediately followed else-if is executed. When the else-if also fails, its successor else-if statement (if any) is executed, and so on. |
4 | nested if construct
You can use one if or else if statement inside another if or else if statement(s). |
5 | select case construct
A select case statement allows a variable to be tested for equality against a list of values. |
6 | nested select case construct
You can use one select case statement inside another select case statement(s). |