12184: 函数求值
Memory Limit:32 MB
Time Limit:1.000 S
Judge Style:Text Compare
Creator:
Submit:1
Solved:0
Description
给定正整数N,函数F(N)表示小于等于N的自然数中1和2的个数之和,例如:1,2,3,4,5,6,7,8,9,10序列中1和2的个数之和为3,因此 F(10)=3。输入N,求F(N)的值,1=<N<=10^100(10的100次方)若F(N)很大,则求F(N)mod20123的值
Sample Input Copy
10
10
Sample Output Copy
3
3