Puzzle 16Double or Nothing
 fn​ ​double_it​(n: i32) ​->​ i32 {
  n * 2
 }
 
 fn​ ​double_it​(n: f32) ​->​ f32 {
  n * 2.0
 }
 
 fn​ ​main​() {
  println!(​"2 * 4 = {}"​, ​double_it​(2));
 }

Guess the Output

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Try to guess what the output is before moving to the next page.

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The program will fail to compile, and you’ll receive the following error message:

 error[E0428]: the name "double_it" is defined multiple times
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