Puzzle 17How Long Is a Vector?
 fn​ ​main​() {
 let​ ​mut​ my_vec = ​Vec​::​with_capacity​(1);
  my_vec​.push​(​"Hello"​);
  println!(​"{}"​, my_vec​.capacity​());
  my_vec​.push​(​"World"​);
  println!(​"{}"​, my_vec​.capacity​());
 }

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 display the following output:

 1
 4
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Discussion

Vectors contain two things: a length indicating ...

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