353 lines
8.2 KiB
C
353 lines
8.2 KiB
C
#include "lib.h"
|
|
|
|
#define DBG 0
|
|
#define PRETTY 1
|
|
|
|
static
|
|
ch input[] = {
|
|
#embed "day6_input.txt"
|
|
};
|
|
|
|
static
|
|
ch test[] = {
|
|
#embed "day6_test.txt"
|
|
};
|
|
|
|
#if PRETTY
|
|
struct line {
|
|
union {
|
|
ch l[24];
|
|
struct {
|
|
ch vs[16];
|
|
ch pad[4];
|
|
num v;
|
|
};
|
|
};
|
|
} __attribute__((aligned(0x40)));
|
|
static_assert(alignof(struct line) == 0x40);
|
|
#endif
|
|
|
|
#if PRETTY
|
|
alignas(0x40) static
|
|
struct line linemem[6];
|
|
struct line *const op_line = &linemem[1];
|
|
struct line *const a_line = &linemem[2];
|
|
struct line *const b_line = &linemem[3];
|
|
struct line *const result_line = &linemem[4];
|
|
#endif
|
|
|
|
static
|
|
num do_part1(size_t file_len, ch file[file_len]) {
|
|
ch *s = file;
|
|
num result = 0;
|
|
|
|
#if PRETTY
|
|
memset(linemem, 0, sizeof(linemem));
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\n");
|
|
#endif
|
|
|
|
s = memchr(s, '\n', file_len);
|
|
num stride = s - file;
|
|
|
|
s = file;
|
|
while (*s != '+' && *s != '*') s += stride;
|
|
num heightb = (s - file);
|
|
num height = (s - file) / stride;
|
|
ch *op = s;
|
|
|
|
#if DBG
|
|
print("STRIDE\t"); printd(stride); print("\n");
|
|
print("HEIGHT\t"); printd(height); print("\n");
|
|
#endif
|
|
|
|
// constructing a pointer more than 1 past the end of an array
|
|
// is UB, sadly, so we'll use offsets
|
|
num op_off = op - file;
|
|
s = file;
|
|
do {
|
|
num ledge_off = op_off - heightb;
|
|
if (s[op_off] == '+') {
|
|
num a = 0;
|
|
num rem = height;
|
|
#if PRETTY
|
|
op_line->vs[15] = '+';
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
do {
|
|
ch *t = s + ledge_off;
|
|
while (*t < '0') t++;
|
|
num b = grabnum(t, NULL);
|
|
#if PRETTY
|
|
b_line->v = b;
|
|
snprintd(b, 16, b_line->vs);
|
|
#endif
|
|
#if DBG
|
|
if (rem < height) { print("\t+\t"); }
|
|
printd(b);
|
|
#endif
|
|
a += b;
|
|
#if PRETTY
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
#endif
|
|
ledge_off += stride;
|
|
rem--;
|
|
} while (rem);
|
|
result += a;
|
|
#if PRETTY
|
|
result_line->v = result;
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\t= "); printd(a); print("\n");
|
|
#endif
|
|
} else if (s[op_off] == '*') {
|
|
num a = 1;
|
|
#if PRETTY
|
|
op_line->vs[15] = '*';
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
num rem = height;
|
|
do {
|
|
ch *t = s + ledge_off;
|
|
while (*t < '0') t++;
|
|
num b = grabnum(t, NULL);
|
|
#if PRETTY
|
|
b_line->v = b;
|
|
snprintd(b, 16, b_line->vs);
|
|
#endif
|
|
#if DBG
|
|
if (rem < height) { print("\t*\t"); }
|
|
printd(b);
|
|
#endif
|
|
a *= b;
|
|
#if PRETTY
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
#endif
|
|
ledge_off += stride;
|
|
rem--;
|
|
} while (rem);
|
|
result += a;
|
|
#if PRETTY
|
|
result_line->v = result;
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\t= "); printd(a); print("\n");
|
|
#endif
|
|
}
|
|
#if DBG
|
|
else {
|
|
print("INVALID OP\n");
|
|
exit_group(-1);
|
|
}
|
|
#endif
|
|
op_off++;
|
|
while (op_off < file_len) {
|
|
if (s[op_off] == '+' || s[op_off] == '*')
|
|
break;
|
|
op_off++;
|
|
}
|
|
} while (op_off < file_len);
|
|
|
|
#if PRETTY
|
|
*op_line = (struct line){ };
|
|
*a_line = (struct line){ };
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
|
|
return result;
|
|
}
|
|
|
|
static
|
|
num do_part2(size_t file_len, unsigned char file[file_len]) {
|
|
ch *s = file;
|
|
num result = 0;
|
|
|
|
#if PRETTY
|
|
memset(linemem, 0, sizeof(linemem));
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\n");
|
|
#endif
|
|
|
|
s = memchr(s, '\n', file_len);
|
|
num stride = s - file;
|
|
|
|
s = file;
|
|
while (*s != '+' && *s != '*') s += stride;
|
|
num heightb = (s - file);
|
|
num height = (s - file) / stride;
|
|
ch *op = s;
|
|
|
|
#if DBG
|
|
print("STRIDE\t"); printd(stride); print("\n");
|
|
print("HEIGHT\t"); printd(height); print("\n");
|
|
#endif
|
|
|
|
// constructing a pointer more than 1 past the end of an array
|
|
// is UB, sadly, so we'll use offsets
|
|
num fop_off = op - file;
|
|
num prev_op_off = fop_off + stride - 1;
|
|
s = file;
|
|
do {
|
|
// we don't need to do these in the same order as the example
|
|
// because both these operations are commutative.
|
|
// but you know what? we can anyway. for fun. and pretty output
|
|
num op_off = prev_op_off - 1;
|
|
while (s[op_off] != '+' && s[op_off] != '*' && s[op_off] != '\n')
|
|
op_off--;
|
|
num ledge_off = op_off - heightb;
|
|
num redge_off = (s[prev_op_off] == '\n' ? -1 : -2) + prev_op_off - heightb;
|
|
if (s[op_off] == '+') {
|
|
num a = 0;
|
|
num rem = redge_off - ledge_off + 1;
|
|
num frem = rem;
|
|
#if PRETTY
|
|
op_line->vs[15] = '+';
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
do {
|
|
num b = 0;
|
|
ch *t = s + redge_off;
|
|
for (num i = height; i; i--,t+=stride) {
|
|
if (*t >= '0') {
|
|
b *= 10;
|
|
b += *t - '0';
|
|
}
|
|
}
|
|
#if PRETTY
|
|
b_line->v = b;
|
|
snprintd(b, 16, b_line->vs);
|
|
#endif
|
|
#if DBG
|
|
if (rem < frem) { print("\t+\t"); }
|
|
printd(b);
|
|
#endif
|
|
a += b;
|
|
redge_off--;
|
|
rem--;
|
|
} while (rem);
|
|
result += a;
|
|
#if PRETTY
|
|
result_line->v = result;
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\t=\t"); printd(a); print("\n");
|
|
#endif
|
|
} else if (s[op_off] == '*') {
|
|
num a = 1;
|
|
num rem = redge_off - ledge_off + 1;
|
|
num frem = rem;
|
|
#if PRETTY
|
|
op_line->vs[15] = '*';
|
|
a_line->v = a;
|
|
snprintd(a, 16, a_line->vs);
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
do {
|
|
num b = 0;
|
|
ch *t = s + redge_off;
|
|
for (num i = height; i; i--,t+=stride) {
|
|
if (*t >= '0') {
|
|
b *= 10;
|
|
b += *t - '0';
|
|
}
|
|
}
|
|
#if PRETTY
|
|
b_line->v = b;
|
|
snprintd(b, 16, b_line->vs);
|
|
#endif
|
|
#if DBG
|
|
if (rem < frem) { print("\t*\t"); }
|
|
printd(b);
|
|
#endif
|
|
a *= b;
|
|
redge_off--;
|
|
rem--;
|
|
} while (rem);
|
|
result += a;
|
|
#if PRETTY
|
|
result_line->v = result;
|
|
snprintd(result, 16, result_line->vs);
|
|
#endif
|
|
#if DBG
|
|
print("\t=\t"); printd(a); print("\n");
|
|
#endif
|
|
}
|
|
#if DBG
|
|
else {
|
|
print("INVALID OP\n");
|
|
exit_group(-1);
|
|
}
|
|
#endif
|
|
prev_op_off = op_off;
|
|
} while (prev_op_off != fop_off);
|
|
|
|
#if PRETTY
|
|
*op_line = (struct line){ };
|
|
*a_line = (struct line){ };
|
|
*b_line = (struct line){ };
|
|
#endif
|
|
|
|
return result;
|
|
}
|
|
|
|
#define RUN_TEST1 0
|
|
#define RUN_PART1 0
|
|
#define RUN_TEST2 1
|
|
#define RUN_PART2 1
|
|
|
|
#define TEST1_EXPECT 4277556
|
|
#define TEST2_EXPECT 3263827
|
|
|
|
void run() {
|
|
#if RUN_TEST1
|
|
print("PART 1 TEST: ");
|
|
if (num v = do_part1(countof(test), test); v != TEST1_EXPECT) {
|
|
print("FAILED (got ");
|
|
printd(v);
|
|
print(", expected " xstr(TEST1_EXPECT) ")\n");
|
|
} else {
|
|
print("PASSED\n");
|
|
}
|
|
#endif
|
|
|
|
#if RUN_PART1
|
|
print("PART 1 RESULT: ");
|
|
printd(do_part1(countof(input), input));
|
|
print("\n");
|
|
#endif
|
|
|
|
#if RUN_TEST2
|
|
print("PART 2 TEST: ");
|
|
if (num v = do_part2(countof(test), test); v != TEST2_EXPECT) {
|
|
print("FAILED (got ");
|
|
printd(v);
|
|
print(", expected " xstr(TEST2_EXPECT) ")\n");
|
|
} else {
|
|
print("PASSED\n");
|
|
}
|
|
#endif
|
|
|
|
#if RUN_PART2
|
|
print("PART 2 RESULT: ");
|
|
printd(do_part2(countof(input), input));
|
|
print("\n");
|
|
#endif
|
|
|
|
exit_group(0);
|
|
}
|