Number Sequence
Time Limit: 1000ms Memory limit: 65536K 有疑问？点这里^_^
题目描述
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).
输入
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.
输出
For each test case, print the value of f(n) on a single line.
示例输入
1 1 3 1 2 10 0 0 0
示例输出
2 5
提示
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来源
示例程序
#include<iostream>
#include<algorithm>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
using namespace std;
int k[100000001];
int main()
{
int a,b,n;
while(scanf("%d%d%d",&a,&b,&n)!=EOF)
{
int x=100000001;
if(a==0 && b==0 && n==0)
{
break;
}
k[1]=1;
k[2]=1;
for(int i=3; i<=n; i++)
{
k[i]=(a*k[i-1]+b*k[i-2])%7;
if(k[i-1]==1 && k[i]==1)
{
x=i-2;
break;
}
}
printf("%d\n",k[(n)%x]);
}
return 0;
}
