62 lines
1.1 KiB
Go
62 lines
1.1 KiB
Go
package main
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import (
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"errors"
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"fmt"
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)
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func Run(code []int16) error {
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if len(code) != 100 {
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return errors.New("Code must be exactly 100 mailboxes long")
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}
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// for i, x := range code {
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// fmt.Printf("%d: %d\n", i, x)
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// }
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// fmt.Println()
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var accumulator int16 = 0
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pc := 0
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for pc >= 0 && pc < len(code) {
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i := code[pc]
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arg := i % 100
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pc++
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switch i - arg {
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case IHALT:
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return nil
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case IADD:
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accumulator += code[arg]
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case ISUBTRACT:
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accumulator -= code[arg]
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case ISTORE:
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code[arg] = accumulator
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case ILOAD:
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accumulator = code[arg]
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case IBRANCH:
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pc = int(i % 100)
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case IBRANCH_IF_ZERO:
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if accumulator == 0 {
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pc = int(arg)
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}
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case IBRANCH_IF_POSITIVE:
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if accumulator > 0 {
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pc = int(arg)
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}
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case IIO:
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switch arg {
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case IO_INPUT:
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fmt.Printf("Input: ")
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fmt.Scanf("%d\n", &accumulator)
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case IO_OUTPUT:
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fmt.Printf("Output: %d\n", accumulator)
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}
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default:
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e := fmt.Sprintf("Unsupported instruction %d at %d", i, pc)
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return errors.New(e)
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}
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}
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return errors.New("Program counter ran away")
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}
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