aboutsummaryrefslogtreecommitdiff
path: root/nth_tribonacci_number.py
diff options
context:
space:
mode:
authorjack <[email protected]>2024-06-14 13:13:15 -0600
committerjack <[email protected]>2024-06-14 13:13:15 -0600
commitd343a3b18dbaca9297d4f7b2280c4a16f0a5c8aa (patch)
tree96df922dae2a5073d9a50ea70c7aae6aa37e3ebe /nth_tribonacci_number.py
downloadleetcode-d343a3b18dbaca9297d4f7b2280c4a16f0a5c8aa.tar.gz
leetcode-d343a3b18dbaca9297d4f7b2280c4a16f0a5c8aa.zip
initial
Diffstat (limited to 'nth_tribonacci_number.py')
-rw-r--r--nth_tribonacci_number.py29
1 files changed, 29 insertions, 0 deletions
diff --git a/nth_tribonacci_number.py b/nth_tribonacci_number.py
new file mode 100644
index 0000000..c647286
--- /dev/null
+++ b/nth_tribonacci_number.py
@@ -0,0 +1,29 @@
+# 1137. N-th Tribonacci Number
+
+"""
+the tribonacci sequence t^n is defined as follows
+t0 = 0, t1 = 1, t2 = 1, & tn+3 = tn + tn+1 + tn+2 for n >= 0
+given n, return value of tn
+eg.
+n = 4, output: 4
+t3 = 0 + 1 + 1 = 2
+t4 = 1 + 1 + 2 = 4
+"""
+
+
+class Solution(object):
+ def tribonacci(self, n):
+ """
+ :type n: int
+ :rtype: int
+ """
+ a, b, c = 1, 0, 0
+ for _ in range(n):
+ a, b, c = b, c, a + b + c
+ return c
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ print(obj.tribonacci(4))
+ print(obj.tribonacci(25))