Source code for submission s1157

Go to diff to previous submission

#include <stdlib.h>
#include <stdio.h>
 
#define NOT_VISITED -1
 
int R, C, GR, GC, LR, LC;
/* R, C ... area size */
int area[102][102]; /* R-major */
 
typedef struct {int r, c;} point;
typedef struct {point list[102*102]; int len;} data;
 
data aa, bb;
 
int in_grid(point x)
{
	int rv = (x.r >= 1 && x.r <= R && x.c >= 1 && x.c <= C);
	/*printf("%d,%d = %d (R=%d, C=%d)\n", x.r, x.c, rv, R, C);*/
	return rv;
}
 
int main(void)
{
	int i, step, row, col, j;
	point *p;
	int *len_ptr;
	point dest[8];
	int flag;
	data *a, *b, *tmp;
 
	while (scanf("%d %d %d %d %d %d ", &R, &C, &GR, &GC, &LR, &LC) == 6) {
		a = &aa;
		b = &bb;
		for (i = 0; i < 102*102; ++i)
			((int*)(area))[i] = NOT_VISITED;
 
		if (GR == LR && GC == LC) {
			printf("0\n");
			continue;
		}
 
		area[GR][GC] = 0;
 
		a->len = 0;
		b->len = 0;
 
		a->list[0].r = GR;
		a->list[0].c = GC;
		a->len = 1;
 
		for (step = 1; ; ++step)
		{
			b->len = 0;
			flag = 0;
			for (i = 0; i < a->len; ++i)
			{
				row = a->list[i].r;
				col = a->list[i].c;
				/*
				dest = { {row+1, col+2}, {row+1, col-2}, {row-1, col+2}, {row-1, col-2},
						 {row+2, col+1}, {row+2, col-1}, {row-2, col+1}, {row-2, col-1} };
				*/
				dest[0].r = row+1;
				dest[0].c = col+2;
 
				dest[1].r = row-1;
				dest[1].c = col+2;
 
				dest[2].r = row+1;
				dest[2].c = col-2;
 
				dest[3].r = row-1;
				dest[3].c = col-2;
 
				dest[4].r = row+2;
				dest[4].c = col+1;
 
				dest[5].r = row-2;
				dest[5].c = col+1;
 
				dest[6].r = row+2;
				dest[6].c = col-1;
 
				dest[7].r = row-2;
				dest[7].c = col-1;
 
 
				for (j = 0; j < 8; ++j)
				{
					if (in_grid(dest[j]))
					{
						if (area[ dest[j].r ][ dest[j].c ] == NOT_VISITED) {
							/*printf("setting flag\n");*/
							area[ dest[j].r ][ dest[j].c ] = step;
							flag = 1;
							b->list[ b->len++ ] = dest[j];
							/*printf("r=%d, c=%d, LR=%d, LC=%d\n", dest[j].r, dest[j].c, LR, LC);*/
							if (dest[j].r == LR && dest[j].c == LC) {
								printf("%d\n", step);
								goto endloop;
							}
						}
					}
				}
 
			}
			if (flag == 0) {
				printf("impossible\n");
				goto endloop;
			}
			tmp = b;
			b = a;
			a = tmp;
		}
endloop:
	;
	}
	return 0;
}
 
 

Diff to submission s1104

--- c4.s1104.cteam007.grasshop.c.0.grasshop.c
+++ c4.s1157.cteam007.grasshop.c.0.grasshop.c
@@ -8,5 +8,5 @@
 int area[102][102]; /* R-major */
 
-typedef struct {unsigned char r, c;} point;
+typedef struct {int r, c;} point;
 typedef struct {point list[102*102]; int len;} data;
 
@@ -15,5 +15,7 @@
 int in_grid(point x)
 {
-        return x.r >= 1 && x.r <= R && x.c >= 1 && x.c <= C;
+        int rv = (x.r >= 1 && x.r <= R && x.c >= 1 && x.c <= C);
+        /*printf("%d,%d = %d (R=%d, C=%d)\n", x.r, x.c, rv, R, C);*/
+        return rv;
 }
 
@@ -32,4 +34,10 @@
                 for (i = 0; i < 102*102; ++i)
                         ((int*)(area))[i] = NOT_VISITED;
+                
+                if (GR == LR && GC == LC) {
+                        printf("0\n");
+                        continue;
+                }
+                
                 area[GR][GC] = 0;
                 
@@ -80,9 +88,12 @@
                                 for (j = 0; j < 8; ++j)
                                 {
-                                        if (in_grid(dest[j])) {
+                                        if (in_grid(dest[j]))
+                                        {
                                                 if (area[ dest[j].r ][ dest[j].c ] == NOT_VISITED) {
+                                                        /*printf("setting flag\n");*/
                                                         area[ dest[j].r ][ dest[j].c ] = step;
                                                         flag = 1;
                                                         b->list[ b->len++ ] = dest[j];
+                                                        /*printf("r=%d, c=%d, LR=%d, LC=%d\n", dest[j].r, dest[j].c, LR, LC);*/
                                                         if (dest[j].r == LR && dest[j].c == LC) {
                                                                 printf("%d\n", step);