blob: 3fe5b3cea997acfe1abb439b9bd27a98f29a38e6 (
plain) (
blame)
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
|
package main
import "fmt"
func countFib(n int64) int64 {
f := make([]int64, n+1)
f[0] = 0
f[1] = 1
f[2] = 2
f[3] = 5
for i := int64(4); i <= n; i++ {
f[i] = (2*f[i-1] + f[i-3]) % 1000000007
}
return f[n]
}
func numTilings(n int) int {
if n <= 2 {
return n
}
return int(countFib(int64(n)))
}
func main() {
// fmt.Println(numTilings(10))
// fmt.Println(numTilings(1))
fmt.Println(numTilings(2))
}
|