0f5b63d86f
Fix #2068 - Army of Functions Fix #2070 - Typo Fix #2056 - Grammatical Error Fix #2074 - Remove semi-colon after function declaration
33 lines
717 B
Markdown
33 lines
717 B
Markdown
The reason is that prompt returns user input as a string.
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So variables have values `"1"` and `"2"` respectively.
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```js run
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let a = "1"; // prompt("First number?", 1);
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let b = "2"; // prompt("Second number?", 2);
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alert(a + b); // 12
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```
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What we should do is to convert strings to numbers before `+`. For example, using `Number()` or
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prepending them with `+`.
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For example, right before `prompt`:
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```js run
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let a = +prompt("First number?", 1);
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let b = +prompt("Second number?", 2);
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alert(a + b); // 3
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```
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Or in the `alert`:
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```js run
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let a = prompt("First number?", 1);
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let b = prompt("Second number?", 2);
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alert(+a + +b); // 3
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```
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Using both unary and binary `+` in the latest code. Looks funny, doesn't it?
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