Farmer John's N cows are standing in a row, as they have a tendency to do from time to time. Each cow is labeled with a distinct integer ID number so FJ can tell them apart. FJ would like to take a photo of a contiguous group of cows but, due to a traumatic childhood incident involving the numbers 1…6, he only wants to take a picture of a group of cows if their IDs add up to a multiple of 7.
Please help FJ determine the size of the largest group he can photograph.
The first line of input contains N(1≤N≤50,000). The next N lines each contain the N integer IDs of the cows (all are in the range 0…1,000,000
).
给定长度为N的数列A,求A最长的连续子序列,满足子序列中元素的和是7的倍数。输出最大的长度。如果不存在满
足条件的子序列,输出0。1 ≤ N ≤ 50000, 0 ≤ A_i ≤ 10 ^ 6