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1 | #include <stdio.h> |
2 | #include <stdlib.h> |
3 | #include <string.h> |
4 | |
5 | #include <mLib/alloc.h> |
6 | #include <mLib/darray.h> |
7 | #include <mLib/dstr.h> |
8 | #include <mLib/quis.h> |
9 | #include <mLib/report.h> |
10 | |
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11 | #include "gf.h" |
12 | #include "gfreduce.h" |
13 | #include "mp.h" |
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14 | |
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15 | #include "factor.h" |
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16 | |
17 | static int primitivep(fact_v *f, mp *p) |
18 | { |
19 | gfreduce r; |
20 | unsigned i; |
21 | mp *x = MP_NEW; |
22 | int rc = 1; |
23 | |
24 | if (!gf_irreduciblep(p)) |
25 | return (0); |
26 | #ifdef DEBUG |
27 | MP_PRINTX("p", p); |
28 | #endif |
29 | gfreduce_create(&r, p); |
30 | for (i = 0; i < DA_LEN(f); i++) { |
31 | x = gfreduce_exp(&r, x, MP_TWO, DA(f)[i].r); |
32 | #ifdef DEBUG |
33 | MP_PRINT(" r", DA(f)[i].r); |
34 | MP_PRINTX(" x", x); |
35 | #endif |
36 | if (MP_EQ(x, MP_ONE)) { |
37 | rc = 0; |
38 | break; |
39 | } |
40 | } |
41 | gfreduce_destroy(&r); |
42 | MP_DROP(x); |
43 | return (rc); |
44 | } |
45 | |
46 | static int dofip(fact_v *f, unsigned m, mp **p, unsigned n, unsigned x) |
47 | { |
48 | unsigned i; |
49 | |
50 | for (i = n + 1; i < x; i++) { |
51 | *p = mp_setbit(*p, *p, i); |
52 | if (n ? dofip(f, m, p, n - 1, i) : primitivep(f, *p)) |
53 | return (1); |
54 | *p = mp_clearbit(*p, *p, i); |
55 | } |
56 | return (0); |
57 | } |
58 | |
59 | static mp *fip(fact_v *f, unsigned m) |
60 | { |
61 | mp *p = MP_ONE; |
62 | unsigned n; |
63 | |
64 | p = mp_setbit(p, p, m); |
65 | n = 0; |
66 | while (!dofip(f, m, &p, n, m)) |
67 | n += 2; |
68 | return (p); |
69 | } |
70 | |
71 | static void findprim(unsigned m) |
72 | { |
73 | fact_v f = DA_INIT; |
74 | mp *q = mp_lsl(MP_NEW, MP_ONE, m); |
75 | mp *p; |
76 | unsigned i; |
77 | |
78 | q = mp_sub(q, q, MP_ONE); |
79 | factor(q, &f); |
80 | |
81 | #ifdef DEBUG |
82 | { |
83 | size_t i; |
84 | for (i = 0; i < DA_LEN(&f); i++) { |
85 | mp_writefile(DA(&f)[i].p, stdout, 10); |
86 | printf("^%u = ", DA(&f)[i].e); |
87 | mp_writefile(DA(&f)[i].n, stdout, 10); |
88 | fputs(" (", stdout); |
89 | mp_writefile(DA(&f)[i].r, stdout, 10); |
90 | fputs(")\n", stdout); |
91 | } |
92 | } |
93 | #endif |
94 | |
95 | p = fip(&f, m); |
96 | MP_PRINTX("p", p); |
97 | for (i = m + 1; i--; ) { |
98 | if (mp_testbit(p, i)) |
99 | printf("%u ", i); |
100 | } |
101 | putchar('\n'); |
102 | mp_drop(p); |
103 | mp_drop(q); |
104 | freefactors(&f); |
105 | } |
106 | |
107 | int main(int argc, char *argv[]) |
108 | { |
109 | ego(argv[0]); |
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110 | if (argc != 2) { |
111 | fprintf(stderr, "Usage: %s M\n", QUIS); |
112 | exit(1); |
113 | } |
114 | findprim(atoi(argv[1])); |
115 | return (0); |
116 | } |