3fb4f86a79
Step 7 of the exercise instruction wants us to "slice only the first 1000 elements of the array", not slicing after the first 1000 elements of the array.
63 lines
1.3 KiB
Go
63 lines
1.3 KiB
Go
// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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// For more tutorials : https://learngoprogramming.com
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// In-person training : https://www.linkedin.com/in/inancgumus/
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// Follow me on twitter: https://twitter.com/inancgumus
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package main
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import (
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"fmt"
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"runtime"
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"runtime/debug"
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"unsafe"
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)
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const size = 1e7
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func main() {
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debug.SetGCPercent(-1)
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report("initial memory usage")
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var array [size]int
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report("after declaring an array")
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array2 := array
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report("after copying the array")
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passArray(array)
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slice1 := array[:]
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slice2 := array[:1e3]
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slice3 := array[1e3:1e4]
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report("after slicings")
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passSlice(slice3)
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fmt.Println()
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fmt.Printf("Array's size : %d bytes.\n", unsafe.Sizeof(array))
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fmt.Printf("Array2's size: %d bytes.\n", unsafe.Sizeof(array2))
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fmt.Printf("Slice1's size: %d bytes.\n", unsafe.Sizeof(slice1))
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fmt.Printf("Slice2's size: %d bytes.\n", unsafe.Sizeof(slice2))
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fmt.Printf("Slice3's size: %d bytes.\n", unsafe.Sizeof(slice3))
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}
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func passArray(items [size]int) {
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items[0] = 100
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report("inside passArray")
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}
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func passSlice(items []int) {
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report("inside passSlice")
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}
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func report(msg string) {
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var m runtime.MemStats
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runtime.ReadMemStats(&m)
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fmt.Printf("[%s]\n", msg)
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fmt.Printf("\t> Memory Usage: %v KB\n", m.Alloc/1024)
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}
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