n, m, p = gets.split.map(&:to_i)
ds = (1..m).map{ gets.to_i }.sort
ds << ds.shift + n until p < ds[0] 

a = n - (ds[0] - p)
b = ds[-1] - p 

min = [a, b].min
ds.each_cons(2){|x, y|
    cost = x - p + (n - (y - x)) 
    min = cost if cost < min 
    cost = (p + n - y) + (n - (y - x)) 
    min = cost if cost < min 
}

p min * 100 