Number Sequence
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 147161 Accepted Submission(s):
35755
Problem Description
A number sequence is defined as follows:
f(1) = 1, f(2) = 1, f(n) = (A * f(n - 1) + B * f(n - 2)) mod 7.
Given A, B, and n, you are to calculate the value of f(n).
f(1) = 1, f(2) = 1, f(n) = (A * f(n - 1) + B * f(n - 2)) mod 7.
Given A, B, and n, you are to calculate the value of f(n).
Input
The input consists of multiple test cases. Each test
case contains 3 integers A, B and n on a single line (1 <= A, B <= 1000, 1
<= n <= 100,000,000). Three zeros signal the end of input and this test
case is not to be processed.
Output
For each test case, print the value of f(n) on a single
line.
Sample Input
1 1 3
1 2 10
0 0 0
Sample Output
2
5
Author
CHEN, Shunbao
Source
Recommend
#include <string.h> #include <iostream> #include <algorithm> #include <stdlib.h> #include <stdio.h> using namespace std; int main() { int a,b,n,i,data[1005]; while (cin>>a>>b>>n&&a&&b&&n) { data[1]=1; data[2]=1; for (i=3;i<=1000;i++) { data[i]=((a*data[i-1]%7)+((b*data[i-2]%7%7)))%7; if (data[i-1]==1&&data[i]==1) //if(data[i-1])意思是只要是正数就行 break; } data[0]=data[i-2]; cout<<data[n%(i-2)]<<endl; } return 0; }