27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
(void)len; // unused argument
struct TextGrid tg;
tg.data = data;
tg.cols = strchr(data, '\n') - data + 1;
tg.rows = tg.cols - 1; // rows includes the '\n'
unsigned anti[512][2]; // locations of antinodes; col at index 0, row at 1
unsigned nanti = 0;
char *p = data;
while (*p) {
while ((*p == '.') || (*p == '\n')) p++;
if (*p) {
// p points to an antenna
unsigned prow = TGrow(&tg, p), pcol = TGcol(&tg, p);
char *q = strchr(p+1, *p);
while (q) {
// q points to an antenna of the same type as p
unsigned qrow = TGrow(&tg, q), qcol = TGcol(&tg, q);
int deltarow = (int)qrow - (int)prow;
int deltacol = (int)qcol - (int)pcol;
int anticol = (int)pcol - deltacol;
int antirow = (int)prow - deltarow;
if (TGvalid(&tg, (unsigned)anticol, (unsigned)antirow) && (*TGcharptr(&tg, (unsigned)anticol, (unsigned)antirow) != '\n')) {
unsigned *ff = antinode_find(anti, nanti, (unsigned)anticol, (unsigned)antirow);
if (!ff) {
anti[nanti][0] = (unsigned)anticol;
anti[nanti++][1] = (unsigned)antirow;
}
}
anticol = (int)qcol + deltacol;
antirow = (int)qrow + deltarow;
if (TGvalid(&tg, (unsigned)anticol, (unsigned)antirow) && (*TGcharptr(&tg, (unsigned)anticol, (unsigned)antirow) != '\n')) {
unsigned *ff = antinode_find(anti, nanti, (unsigned)anticol, (unsigned)antirow);
if (!ff) {
anti[nanti][0] = (unsigned)anticol;
anti[nanti++][1] = (unsigned)antirow;
}
}
q = strchr(q+1, *p); // next antenna of this type
}
p += 1;
}
}
printf("There are %u antinodes within the map.\n", nanti);
}
/* === aoc202407 =======================================================
Part one looks easy
Part two also easy
===================================================================== */
|
>
>
>
>
|
>
|
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
|
>
|
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
(void)len; // unused argument
struct TextGrid tg;
tg.data = data;
tg.cols = strchr(data, '\n') - data + 1;
tg.rows = tg.cols - 1; // rows includes the '\n'
unsigned anti[512][2]; // locations of antinodes; col at index 0, row at 1
unsigned nanti = 0;
unsigned anti2[1024][2]; // locations of antinodes; col at index 0, row at 1
unsigned nanti2 = 0;
char *p = data;
while (*p) {
while ((*p == '.') || (*p == '\n')) p++;
if (*p) {
// p points to an antenna
unsigned prow = TGrow(&tg, p), pcol = TGcol(&tg, p);
char *q = strchr(p+1, *p);
while (q) {
// q points to an antenna of the same type as p
unsigned qrow = TGrow(&tg, q), qcol = TGcol(&tg, q);
int deltarow = (int)qrow - (int)prow;
int deltacol = (int)qcol - (int)pcol;
int anticol = (int)pcol - deltacol;
int antirow = (int)prow - deltarow;
unsigned *ff;
if (TGvalid(&tg, (unsigned)anticol, (unsigned)antirow) && (*TGcharptr(&tg, (unsigned)anticol, (unsigned)antirow) != '\n')) {
ff = antinode_find(anti, nanti, (unsigned)anticol, (unsigned)antirow);
if (!ff) {
anti[nanti][0] = (unsigned)anticol;
anti[nanti++][1] = (unsigned)antirow;
}
}
anticol = (int)qcol + deltacol;
antirow = (int)qrow + deltarow;
if (TGvalid(&tg, (unsigned)anticol, (unsigned)antirow) && (*TGcharptr(&tg, (unsigned)anticol, (unsigned)antirow) != '\n')) {
ff = antinode_find(anti, nanti, (unsigned)anticol, (unsigned)antirow);
if (!ff) {
anti[nanti][0] = (unsigned)anticol;
anti[nanti++][1] = (unsigned)antirow;
}
}
int k;
// q - delta is p; q -2delta is one afterwards, etc
// add q - (k)delta to anti2 while valid
k = 1;
while (TGvalid(&tg, (unsigned)((int)qcol-k*deltacol), (unsigned)((int)qrow-k*deltarow)) && (*TGcharptr(&tg, (unsigned)((int)qcol-k*deltacol), (unsigned)((int)qrow-k*deltarow)) != '\n')) {
ff = antinode_find(anti2, nanti2, (unsigned)((int)qcol-k*deltacol), (unsigned)((int)qrow-k*deltarow));
if (!ff) {
anti2[nanti2][0] = (unsigned)((int)qcol-k*deltacol);
anti2[nanti2++][1] = (unsigned)((int)qrow-k*deltarow);
}
k++;
}
// p + delta is q; p +2delta is one afterwards, etc
// add p + (k)delta to anti2 while valid
k = 1;
while (TGvalid(&tg, (unsigned)((int)pcol+k*deltacol), (unsigned)((int)prow+k*deltarow)) && (*TGcharptr(&tg, (unsigned)((int)pcol+k*deltacol), (unsigned)((int)prow+k*deltarow)) != '\n')) {
ff = antinode_find(anti2, nanti2, (unsigned)((int)pcol+k*deltacol), (unsigned)((int)prow+k*deltarow));
if (!ff) {
anti2[nanti2][0] = (unsigned)((int)pcol+k*deltacol);
anti2[nanti2++][1] = (unsigned)((int)prow+k*deltarow);
}
k++;
}
// next antenna of this type
q = strchr(q+1, *p);
}
p += 1;
}
}
printf("There are %u antinodes within the map.\n", nanti);
printf("There are %u resonant antinodes within the map.\n", nanti2);
}
/* === aoc202407 =======================================================
Part one looks easy
Part two also easy
===================================================================== */
|