61 lines
964 B
Go
61 lines
964 B
Go
package main
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import (
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"encoding/binary"
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"io"
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"log"
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"net"
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"protohackers/pkg/conn"
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)
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func main() {
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err := conn.StartSimple(meansToAnEnd)
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if err != nil {
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log.Fatalln(err)
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}
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}
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func meansToAnEnd(c net.Conn) {
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defer c.Close()
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var ledger = make(map[int32]int32)
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buf := make([]byte, 9)
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for {
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if _, err := io.ReadFull(c, buf); err != nil {
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return
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}
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if _, err := c.Write(process(buf, ledger)); err != nil {
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return
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}
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}
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}
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func process(buf []byte, ledger map[int32]int32) []byte {
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i1, i2 := int32(binary.BigEndian.Uint32(buf[1:5])), int32(binary.BigEndian.Uint32(buf[5:]))
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switch buf[0] {
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case 'I':
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ledger[i1] = i2
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case 'Q':
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var c int64
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var t int64
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for k, v := range ledger {
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if i1 <= k && k <= i2 {
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t += int64(v)
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c++
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}
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}
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if c == 0 {
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c = 1 /* Can't divide by zero! */
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}
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mean := t / c
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r := make([]byte, 4)
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binary.BigEndian.PutUint32(r, uint32(mean))
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return r
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default:
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return nil
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}
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return nil
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}
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