import sys

def jumps(elements):
    current = elements[0]
    remaining = len(elements)
    if current == 0:        # base case: can't jump from 0
        return sys.maxint
    elif remaining == 1:    # base case: reached end
        return 0
    else:                   # recursive case
        js = range(1, min(current+1, remaining))
        candidates = map(lambda j: jumps(elements[j:]), js)
        return 1 + min(candidates)

print jumps([0]) == sys.maxint
print jumps([9]) == 0
print jumps([1,3,5,8,9,2,6,7,6,8,9]) == 3
print jumps([1,3,5,0,1,9,1,1,1,1,1,1,1]) == 4