1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
package main
import (
"database/sql"
"flag"
"fmt"
"math/rand"
"os"
"os/exec"
_ "modernc.org/sqlite"
)
var (
verbose = flag.Bool("v", false, "debug output")
file = flag.String("f", "cards", "cards file")
)
func main() {
flag.Parse()
db, err := sql.Open("sqlite", *file)
if err != nil {
panic(err)
}
// Get number of cards
var N int
_ = db.QueryRow("SELECT COUNT(*) FROM cards").Scan(&N)
s := segmentTree{N, make([]int, 4*N)}
// Build segment tree
rows, err := db.Query("SELECT weight FROM cards")
if err != nil {
panic(err)
}
s.build(rows, 0, N-1, 1)
rows.Close()
if *verbose {
fmt.Println(s)
}
// https://stackoverflow.com/questions/14094190/function-similar-to-getchar
// disable input buffering
exec.Command("stty", "-F", "/dev/tty", "cbreak", "min", "1").Run()
// do not display entered characters on the screen
exec.Command("stty", "-F", "/dev/tty", "-echo").Run()
// restore the echoing state when exiting
defer exec.Command("stty", "-F", "/dev/tty", "echo").Run()
for {
// Choose a random card
x := rand.Intn(s.seg[1])
w, i := s.query(x, 0, N-1, 1)
if *verbose {
fmt.Println(s.seg[1])
fmt.Println(x)
fmt.Println(w)
fmt.Println(i)
}
// Get card contents from database
var key, val string
db.QueryRow("SELECT key, val FROM cards WHERE idx=?", i).Scan(&key, &val)
fmt.Println(key)
// Wait for confirmation
var b []byte = make([]byte, 1)
os.Stdin.Read(b)
fmt.Println(val)
// Read user input
os.Stdin.Read(b)
if b[0] == byte('y') {
w >>= 1
} else if b[0] == byte('n') {
w <<= 1
} else {
os.Exit(0)
}
// Update segment tree and database
s.update(i, w, 0, N-1, 1)
_, err = db.Exec("UPDATE cards SET weight=? WHERE idx=?", w, i)
if err != nil {
panic(err)
}
}
}
|
