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C. DZY Loves Fibonacci Numbers
time limit per test
4 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output
In mathematical terms, the sequence Fn of Fibonacci numbers is defined by the recurrence relation
F1?=?1; F2?=?1; Fn?=?Fn?-?1?+?Fn?-?2 (n?>?2).DZY loves Fibonacci numbers very much. Today DZY gives you an array consisting of n integers: a1,?a2,?...,?an. Moreover, there are mqueries, each query has one of the two types:
Help DZY reply to all the queries.
Input
The first line of the input contains two integers n and m (1?≤?n,?m?≤?300000). The second line contains n integers a1,?a2,?...,?an (1?≤?ai?≤?109) ? initial array a.
Then, m lines follow. A single line describes a single query in the format given in the statement. It is guaranteed that for each query inequality 1?≤?l?≤?r?≤?n holds.
Output
For each query of the second type, print the value of the sum on a single line.
Sample test(s)
input
4 41 2 3 41 1 42 1 41 2 42 1 3
output
1712
题意:支持两种操作,1 l r 将 ai 加上第i-l+1项Fibonacci数,l
思路:根据Fibonacci数列的性质,只要知道前两项,那么可以O(1)得到后面任意项的Fibonacci数以及任意前多少项的和,可以用线段树维护每个线段的和以及每段的前两
个Fibonacci数,延迟更新的是每个线段的前两个Fibonacci数(直接累加)