Project Euler:problem Square digit chains

A number chain is created by continuously adding the square of the digits in a number to form a new number until it have be En seen before.

For example,

44→32→13→10→ 1 → 1
85→ →145→42→20→4→16→37→58→

Therefore any chain this arrives at 1 or the become stuck in an endless loop. What are most amazing are that every starting number would eventually arrive at 1 or 89.

How many starting numbers below ten million would arrive at 89?

For a number within 10000000, the sum of the squares of each digit is 9*9*7, that is, the next digit of 9999999 should be 9*9*7

Declares a bool array of size 567, which is marked true when the number finally arrives 89 o'clock

Def nextnum (a):    res=0 while    a!=0:        tmp=a%10        res=res+tmp*tmp        A=A//10    return resres=0num=[ False for I in range (9*9*7+2)]for I in Range (9*9*7+1):    nextn=nextnum (i) while    nextn>i and nextn!=89:        Nextn=nextnum (NEXTN)    if Num[nextn]==true or nextn==89:       res=res+1       num[i]=truefor i in range (9*9*7+ 1,10000000):       if Num[nextnum (i)]==true:           res=res+1print (' res = ', res)

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Project euler:problem Square digit chains