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Simple branchTo draw a simple branch, you use if else . But notice that using if else statement does not guarantee that the output will be a simple branch; it may be possible that the output becomes a multiplex branch. For more information, refer to section3.6.2. The simplest conditional branch is one that has only if. This example is a program to return an absolute value.
if(x < 0) x = -x
By using else you can write process to be executed when condition is false. The next example calculate a square root, and it will print an imaginary unit i if the number is negative:
if(x >= 0) print sqrt(x) else{ print sqrt(-x) print 'i' }
Finally, I am going to explain valid and invalid syntax of if else statement. If true part or false part contains only one command, you do not have to enclose it with { } as in the first example. However, these are both illegal: if(x < 0) x = -x if(x < 0){ x = -x } You can omit both true part and false part. Hence, the following example is OK: if(x >= 0){ }else{ x = -x } if(x < 0){ }else{ } You can insert a newline code before { and after }, and you can put as many spaces as you like. So, the next example is valid. if ( x >= 0 ) { print sqrt(x) } else { print sqrt(-x) print 'i' }
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