B"Polycarp likes numbers that are divisible by 3. He has a huge number s . Polycarp wants to cut from it the maximum number of numbers that are divisible by 3 . To do this, he makes an arbitrary number of vertical cuts between pairs of adjacent digits. As a result, after m such cuts, there will be m+1 parts in total. Polycarp analyzes each of the obtained numbers and finds the number of those that are divisible by 3 . For example, if the original number is s=3121 , then Polycarp can cut it into three parts with two cuts: 3|1|21 . As a result, he will get two numbers that are divisible by 3 . Polycarp can make an arbitrary number of vertical cuts, where each cut is made between a pair of adjacent digits. The resulting numbers cannot contain extra leading zeroes (that is, the number can begin with 0 if and only if this number is exactly one character '0'). For example, 007, 01 and 00099 are not valid numbers, but 90, 0 and 10001 are valid. What is the maximum number of numbers divisible by 3 that Polycarp can obtain? The first line of the input contains a positive integer s . The number of digits of the number s is between 1 and 2 cdot10^5 , inclusive. The first (leftmost) digit is not equal to 0. Print the maximum number of numbers divisible by 3 that Polycarp can get by making vertical cuts in the given number s . In the first example, an example set of optimal cuts on the number is 3|1|21. In the second example, you do not need to make any cuts. The specified number 6 forms one number that is divisible by 3 . In the third example, cuts must be made between each pair of digits. As a result, Polycarp gets one digit 1 and 33 digits 0. Each of the 33 digits 0 forms a number that is divisible by 3 . In the fourth example, an example set of optimal cuts is 2|0|1|9|201|81. The numbers 0 , 9 , 201 and 81 are divisible by 3 . "...