学步园

#include <stdio.h><br /> int main()<br /> {<br /> int i,j,a,b,c,A,B,first,end,f[52];<br /> long n;<br /> while(scanf("%d%d%ld",&A,&B,&n)!=EOF)<br /> {<br /> if(A==0&&B==0&&n==0) break;<br /> f[1]=f[2]=1;<br /> for(a=1,b=1,i=3;i<=51;i++)<br /> {<br /> c=(A*b+B*a)%7;<br /> a=b;<br /> b=c;<br /> f[i]=c;<br /> }<br /> if(n<=50) printf("%d/n",f[n]);<br /> else<br /> {<br /> for(first=end=0,i=2;i<=50;i++)<br /> for(j=1;j<i;j++)<br /> {<br /> if(f[i]==f[j]&&f[i+1]==f[j+1])<br /> {<br /> first=j;<br /> end=i;<br /> }<br /> }<br /> printf("%d/n",f[first+(n-first)%(end-first)]);<br /> }<br /> }<br /> return 0;<br /> }