There is a wonderful country called "-0 country", they only have two numbers of 1 and 0, so when encountering a relatively large number, they have to use many combinations of 1 and 0 to express it, for example : 12 can be expressed as the sum of three numbers 10+1+1, or as the sum of two numbers 11+1, so in the "-0 country", how many numbers should be added at least to express 20120204.
有一个奇妙的国家，叫"-0国"，他们只有1和0两个数字，所以，当遇到比较大的数时，他们就要用好多个1和0组合相加来表示，比如说：12可以表示成三个数的和10+1+1，也可以表示成两个数的和11+1，那么在"-0国"，20120204最少要用多少个数相加来表示．
<result>4</result>