The Tribonacci sequence Tn is defined as follows:
T0 = 0, T1 = 1, T2 = 1, and Tn+3 = Tn + Tn+1 + Tn+2 for n >= 0.
GivenĀ n
, return the value of Tn.
Example 1:
Input: n = 4
Output: 4
Explanation:
T_3 = 0 + 1 + 1 = 2
T_4 = 1 + 1 + 2 = 4
Example 2:
Input: n = 25
Output: 1389537
class Solution {
public int tribonacci(int n) {
if (n <= 1) {
return n;
}
if (n ==2){
return 1;
}
int cache[] = new int [n+1];
cache[1] = 1;
cache[2] = 1;
for(int i=3;i<=n;i++) {
cache[i] = cache[i-1] + cache[i-2] + cache[i-3];
}
return cache[n];
}
}