57 lines
1.2 KiB
Go
57 lines
1.2 KiB
Go
package main
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import (
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"bufio"
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"fmt"
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"os"
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"strconv"
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)
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type Set map[int]struct{}
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// Provide a filename as input, get the result on stdout
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func main() {
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x := 0
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found := false
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seen := Set{0: struct{}{}}
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for {
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x, found = ScanFrequencies(os.Args[1], &seen, x)
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if found {
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break
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}
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fmt.Println("All frequencies scanned, repeating...")
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}
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fmt.Println("Repeat frequency detected, calibration complete: ", x)
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}
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// ScanFrequencies iterates over a list of frequencies (provided as an open
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// file handle), compares against a list of frequencies already seen and a 'current' frequency counter,
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// and returns `true` when a duplicate frequency is found. Integer value returned is the new, adjusted frequency
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func ScanFrequencies(freqFile string, seen *Set, frequency int) (int, bool) {
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file, err := os.Open(os.Args[1])
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if err != nil {
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panic(err)
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}
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duplicateFound := false
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scanner := bufio.NewScanner(file)
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for scanner.Scan() {
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y, err := strconv.Atoi(scanner.Text())
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if err != nil {
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panic(err)
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}
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frequency += y
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if _, ok := (*seen)[frequency]; ok {
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duplicateFound = true
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break
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}
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(*seen)[frequency] = struct{}{}
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}
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file.Close()
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return frequency, duplicateFound
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}
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