def makePowerNonDecreasing(power):
    # Write your code here
    res=0
    gap=0
    while len(power)>1:
        power[1]+=res
        print(power, res)
        if power[1]>=power[0]:
            power.pop(0)
        else:
            gap=power[0]-power[1]
            res+=gap
            power.pop(0)
            power[0]+=gap
        print(power, res)
    return res    

res = makePowerNonDecreasing([3,5,2,6,3])
print(res)