forked from EndlessCheng/codeforces-go
-
Notifications
You must be signed in to change notification settings - Fork 0
/
123D.go
85 lines (80 loc) · 1.56 KB
/
123D.go
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
package main
import (
"bufio"
. "fmt"
"index/suffixarray"
"io"
"reflect"
"unsafe"
)
// github.com/EndlessCheng/codeforces-go
func CF123D(_r io.Reader, out io.Writer) {
max := func(a, b int) int {
if a > b {
return a
}
return b
}
var s []byte
Fscan(bufio.NewReader(_r), &s)
n := len(s)
sa := *(*[]int32)(unsafe.Pointer(reflect.ValueOf(suffixarray.New(s)).Elem().FieldByName("sa").Field(0).UnsafeAddr()))
rank := make([]int, n)
for i := range rank {
rank[sa[i]] = i
}
height := make([]int, n+1)
h := 0
for i, ri := range rank {
if h > 0 {
h--
}
if ri > 0 {
for j := int(sa[ri-1]); i+h < n && j+h < n && s[i+h] == s[j+h]; h++ {
}
}
height[ri] = h
}
type pair struct{ v, i int }
pl := make([]int, n+1)
st := []pair{{-1, 0}}
for i, v := range height {
for {
if top := st[len(st)-1]; top.v < v {
pl[i] = top.i
break
}
st = st[:len(st)-1]
}
st = append(st, pair{v, i})
}
pr := make([]int, n+1)
st = []pair{{-1, n}}
for i := n - 1; i >= 0; i-- {
v := height[i]
for {
if top := st[len(st)-1]; top.v < v {
pr[i] = top.i
break
}
st = st[:len(st)-1]
}
st = append(st, pair{v, i})
}
ans := int64(n) * int64(n+1) / 2
usedSt := []int{0}
for i, v := range height {
for v < usedSt[len(usedSt)-1] {
usedSt = usedSt[:len(usedSt)-1]
}
if v == usedSt[len(usedSt)-1] {
continue
}
usedSt = append(usedSt, v)
l, r := pl[i], pr[i]
h, w := int64(v-max(height[l], height[r])), int64(r-l)
ans += h * w * (w - 1) / 2
}
Fprint(out, ans)
}
//func main() { CF123D(os.Stdin, os.Stdout) }