//p1
n = int(input())
a = 30001
for i in range(n):
    b = input()
    if b[len(b) - 1] == "4" and a > int(b):
        a = int(b)
print(a)

//p2
for i in range(10, 100):
    a = i//10
    b = i%10
    if i==2*a*b:
        print(i)

//p3
import math;
x = float(input())
n = int(input())
a = 0.0
for i in range(0, n + 1):
    b =(-1)**(i)*(x**(2*i+1))/math.factorial(2*i+1)
    a = a + b
print(a)

//p4
m,n = map(int, input().split())
for i in range(m,n+1):
    b = 0
    for q in range(1, i + 1):
        if i % q == 0:
            b = b + q
    print(str(i)+": "+str(b))

//p5
n = int(input())
for i in range(n, 0, -1):
    a = ""
    for q in range(i):
        a = a + "1"
    print(a)

//p6
n = int(input())
for i in range(n + 1, n*2+1):
    for q in range(2, i):
        if i % q == 0:
            break
    else:
        print(i)
        break