int main()
{
FILE *fp;
big e,n,g,a;
brick binst;
int window,nb,bits;
miracl *mip=mirsys(100,0);
n=mirvar(0);
e=mirvar(0);
a=mirvar(0);
g=mirvar(0);
fp=fopen("common.dss","rt");
fscanf(fp,"%d\n",&bits);
mip->IOBASE=16;
cinnum(n,fp);
cinnum(g,fp);
cinnum(g,fp);
mip->IOBASE=10;
printf("modulus is %d bits in length\n",logb2(n));
printf("Enter size of exponent in bits = ");
scanf("%d",&nb);
getchar();
printf("Enter window size in bits (1-10)= ");
scanf("%d",&window);
getchar();
if (!brick_init(&binst,g,n,window,nb))
{
printf("Failed to initialize\n");
return 0;
}
printf("%d big numbers have been precomputed and stored\n",(1<<window));
bigbits(nb,e); /* random exponent */
printf("naive method\n");
powmod(g,e,n,a);
cotnum(a,stdout);
printf("Comb method\n");
pow_brick(&binst,e,a);
brick_end(&binst);
cotnum(a,stdout);
return 0;
}
double powers_precomp(int gb,int eb,big p)
{
int iterations=0;
clock_t start;
double elapsed;
brick binst;
big g,e,w;
char *mem;
mem=(char *)memalloc(3);
g=mirvar_mem(mem,0);
e=mirvar_mem(mem,1);
w=mirvar_mem(mem,2);
bigbits(gb,g);
brick_init(&binst,g,p,WINDOW,eb);
bigbits(eb,e);
start=clock();
do {
pow_brick(&binst,e,w);
iterations++;
elapsed=(clock()-start)/(double)CLOCKS_PER_SEC;
} while (elapsed<MIN_TIME || iterations<MIN_ITERS);
elapsed=1000.0*elapsed/iterations;
printf("P - %8d iterations of %4d/%4d ",iterations,gb,eb);
printf(" %8.2lf ms per iteration\n",elapsed);
brick_end(&binst);
memkill(mem,3);
return elapsed;
}
