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# Uses python3
import sys
# def getFib(n):
# if (n <= 1):
# return n
# fibLst = [None] * (n + 1)
# fibLst[0] = 0
# fibLst[1] = 1
# for j in range(2, n + 1):
# fibLst[j] = fibLst[j - 1] + fibLst[j - 2]
# return fibLst[n]
#
#
# def getFibOptimized(n):
# if (n <= 1):
# return n
# firstFib = 0
# secondFib = 1
# tempHolder = 1
# for _ in range(2, n + 1):
# tempHolder = firstFib + secondFib
# firstFib = secondFib
# secondFib = tempHolder
# return secondFib
def getPisanoPeriod(m):
period = 2
remainder1 = 1
remainder2 = 1
for _ in range(3, 6 * m + 1):
period = period + 1
if (remainder2 == 1) & (remainder1 + remainder2 == m):
break
else:
tempHolder = remainder1 + remainder2
remainder1 = remainder2
if tempHolder >= m:
remainder2 = tempHolder - m
else:
remainder2 = tempHolder
return period
def getFibNModM(n, m):
# https://medium.com/competitive/huge-fibonacci-number-modulo-m-6b4926a5c836
# the above link helped me in improving my code
p = getPisanoPeriod(m)
r = n % p
if r == 0:
return 0
firstN = 0
secondN = 1
tempHolder = 1
for _ in range(2, r + 1):
tempHolder = (firstN + secondN) % m;
firstN = secondN
secondN = tempHolder
# return getFibOptimized(n % p) % m
return secondN
if __name__ == '__main__':
entryNumbers = sys.stdin.read()
tokens = entryNumbers.split()
n = int(tokens[0])
m = int(tokens[1])
print(getFibNModM(n, m))
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