119 lines
2.4 KiB
Markdown
119 lines
2.4 KiB
Markdown
## Which expression increases `n` by 1?
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```go
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var n float64
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```
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1. `n = +1`
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2. `n = n++`
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3. `n = n + 1` *CORRECT*
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4. `++n`
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> **1:** This just assigns 1 to n.
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>
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> **2:** IncDec statement can't be used as an operator.
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>
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> **4:** Go doesn't support prefix incdec notation.
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>
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## Which expression decreases `n` by 1?
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```go
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var n int
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```
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1. `n = -1`
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2. `n = n--`
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3. `n = n - 1` *CORRECT*
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4. `--n`
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> **1:** This just assigns -1 to n.
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>
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> **2:** IncDec statement can't be used as an operator.
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>
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> **4:** Go doesn't support prefix incdec notation.
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>
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## Which code below equals to `n = n + 1`?
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1. `n++` *CORRECT*
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2. `n = n++`
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3. `++n`
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4. `n = n ++ 1`
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> **2:** IncDec statement can't be used as an operator.
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>
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> **3:** Go doesn't support prefix incdec notation.
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>
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> **4:** What's that? ++?
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>
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## Which code below equals to `n = n + 1`?
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1. `n = n++`
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2. `n += 1` *CORRECT*
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3. `++n`
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4. `n = n ++ 1`
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> **1:** IncDec statement can't be used as an operator.
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>
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> **3:** Go doesn't support prefix incdec notation.
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>
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> **4:** What's that? ++?
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>
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## Which code below equals to `n -= 1`?
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1. `n = n--`
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2. `n += 1--`
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3. `n--` *CORRECT*
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4. `--n`
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> **1:** IncDec statement can't be used as an operator.
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>
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> **2:** IncDec statement can't be used as an operator. And also, you can't use it with `1--`. The value should be addressable. You're going to learn what that means soon.
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>
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> **4:** Go doesn't support prefix incdec notation.
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>
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## Which code below divides the `length` by 10?
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1. `length = length // 10`
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2. `length /= 10` *CORRECT*
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3. `length //= 10`
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> **1:** What's that? `//`?
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>
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> **2:** That's right. This equals to: `length = length / 10`
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>
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> **3:** What's that? `//=`?
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>
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## Which code below equals to `x = x % 2`?
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1. `x = x / 2`
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2. `x =% x`
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3. `x %= x` *CORRECT*
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> **1:** This is a division. You need to use the remainder operator.
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>
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> **2:** Close... But, the `%` operator is on the wrong side of the assignment.
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>
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## Which function below converts a string value into a float value?
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1. `fmtconv.ToFloat`
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2. `conv.ParseFloat`
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3. `strconv.ParseFloat` *CORRECT*
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4. `strconv.ToFloat`
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## Which code is correct?
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If you don't remember it, this its function signature:
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```go
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func ParseFloat(s string, bitSize int) (float64, error)
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```
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1. `strconv.ParseFloat("10", 128)`
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2. `strconv.ParseFloat("10", 64)` *CORRECT*
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3. `strconv.ParseFloat("10", "64")`
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4. `strconv.ParseFloat(10, 64)`
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> **1:** There are no 128-bit floating point values in Go (Actually there are, but they only belong to the compile-time).
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> |