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#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int
main(void)
{
FILE *fp;
char cl[5];
int north, east;
int direction = 0;
if (!(fp = fopen("input", "r")))
err(EXIT_FAILURE, "fopen");
north = east = 0;
while (fgets(cl, sizeof(cl), fp) != NULL) {
switch (cl[0]) {
case 'N':
north += atoi(&cl[1]);
break;
case 'E':
east += atoi(&cl[1]);
break;
case 'S':
north -= atoi(&cl[1]);
break;
case 'W':
east -= atoi(&cl[1]);
break;
case 'L':
direction -= atoi(&cl[1]);
goto wrap;
case 'R':
direction += atoi(&cl[1]);
wrap:
/* 0 <= direction < 360 */
if (direction >= 360)
direction -= 360;
else if (direction < 0)
direction += 360;
break;
case 'F':
switch (direction) {
case 0:
east += atoi(&cl[1]);
break;
case 90:
north -= atoi(&cl[1]);
break;
case 180:
east -= atoi(&cl[1]);
break;
case 270:
north += atoi(&cl[1]);
break;
}
break;
}
}
fclose(fp);
/* Absolute value */
if (north < 0)
north = -north;
if (east < 0)
east = -east;
printf("%d\n", north + east);
return EXIT_SUCCESS;
}
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