42 lines
632 B
C++
42 lines
632 B
C++
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#define MAXPRC 4000
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char p[MAXPRC];
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char t[MAXPRC];
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int q;
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main(argc,argv)
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int argc;
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char *argv[];
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{
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long startime, endtime;
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register int i;
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if (argc == 2) {
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sscanf(argv[1],"%d",&q);
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} else {
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printf("Usage: pi [precision]\n");
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exit(55);
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}
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if (q > MAXPRC) {
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printf("Precision too large\n");
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exit(66);
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}
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/* compute pi */
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time(&startime);
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arctan(2);
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arctan(3);
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mul4();
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time(&endtime);
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/* print pi */
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printf("pi = %d.",p[0]);
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for (i = 1; i <= q; i++)
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printf("%d",p[i]);
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printf("\n");
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printf("%ld seconds to compute %d digits of pi\n",endtime-startime,q);
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}
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