56 lines
955 B
Go
56 lines
955 B
Go
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"os"
|
||
|
|
"strconv"
|
||
|
|
)
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
if len(os.Args) < 2 || os.Args[1] == "-help" {
|
||
|
|
fmt.Println("Usage: day25 <row> <col>")
|
||
|
|
fmt.Println(" or: day25 <code number>")
|
||
|
|
}
|
||
|
|
row := mustAtoi(os.Args[1])
|
||
|
|
if len(os.Args) == 2 {
|
||
|
|
fmt.Printf("%d\n", genCodeNum(row))
|
||
|
|
os.Exit(0)
|
||
|
|
}
|
||
|
|
// Must be row/col request
|
||
|
|
col := mustAtoi(os.Args[2])
|
||
|
|
fmt.Printf("%d\n", genCodeNum(codeNumFromRowCol(row, col)))
|
||
|
|
}
|
||
|
|
|
||
|
|
func codeNumFromRowCol(r int, c int) int {
|
||
|
|
if r == 1 {
|
||
|
|
if c == 1 {
|
||
|
|
return 1
|
||
|
|
}
|
||
|
|
return c + codeNumFromRowCol(r, c-1)
|
||
|
|
}
|
||
|
|
if c == 1 {
|
||
|
|
return codeNumFromRowCol(1, (r-1)) + 1
|
||
|
|
}
|
||
|
|
return codeNumFromRowCol((r+1), (c-1)) + 1
|
||
|
|
}
|
||
|
|
|
||
|
|
func genCodeNum(i int) int64 {
|
||
|
|
ret := int64(20151125)
|
||
|
|
for i > 1 {
|
||
|
|
ret *= 252533
|
||
|
|
ret = ret % 33554393
|
||
|
|
i--
|
||
|
|
}
|
||
|
|
return ret
|
||
|
|
}
|
||
|
|
|
||
|
|
func mustAtoi(s string) int {
|
||
|
|
var i int
|
||
|
|
var err error
|
||
|
|
if i, err = strconv.Atoi(s); err != nil {
|
||
|
|
fmt.Println("Tried to atoi " + s)
|
||
|
|
os.Exit(1)
|
||
|
|
}
|
||
|
|
return i
|
||
|
|
}
|