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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#if 0
#define PART part1
#else
#define PART part2
#endif
#if 0
#define FILENAME "sample.txt"
#define SIDE 5
#else
#define FILENAME "input.txt"
#define SIDE 99
#endif
#define MAX(x, y) (((x) > (y)) ? (x) : (y))
int ans = 0;
int table[SIDE][SIDE];
void parse()
{
FILE *fp = fopen(FILENAME, "r");
if(!fp) {
fprintf(stderr, "ERROR: Could not opne file: %s\n", FILENAME);
exit(1);
}
char line[256];
int col = 0;
while(fgets(line, sizeof(line), fp))
{
assert(col < SIDE);
for(int i = 0; i < SIDE; i++)
table[i][col] = line[i] - '0';
col++;
}
fclose(fp);
}
void part1()
{
ans = (SIDE*4) - 4;
for(int y = 1; y < (SIDE-1); y++)
for(int x = 1; x < (SIDE-1); x++)
{
int cur = table[x][y];
// row left
int rl = 1;
for(int i = 0; i < x; i++)
rl &= cur > table[i][y];
// row right
int rr = 1;
for(int i = (x+1); i < SIDE; i++)
rr &= cur > table[i][y];
// col up
int cu = 1;
for(int i = 0; i < y; i++)
cu &= cur > table[x][i];
// col down
int cd = 1;
for(int i = (y+1); i < SIDE; i++)
cd &= cur > table[x][i];
if(rl || rr || cu || cd) ans++;
}
}
void part2()
{
for(int y = 1; y < (SIDE-1); y++)
for(int x = 1; x < (SIDE-1); x++)
{
int cur = table[x][y];
// row left
int rl = 0;
for(int i = (x-1); i >= 0; i--) {
rl++;
if(cur <= table[i][y]) break;
}
// row right
int rr = 0;
for(int i = (x+1); i < SIDE; i++) {
rr++;
if(cur <= table[i][y]) break;
}
// col up
int cu = 0;
for(int i = (y-1); i >= 0; i--) {
cu++;
if(cur <= table[x][i]) break;
}
// col down
int cd = 0;
for(int i = (y+1); i < SIDE; i++) {
cd++;
if(cur <= table[x][i]) break;
}
ans = MAX(ans, rl * rr * cu * cd);
}
}
int main(void)
{
parse();
PART();
printf("%d\n", ans);
return 0;
}
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