Submission #61387994

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Source Code Expand

h, w = map(int, input().split())
s = []
for i in range(h):
    si = input()
    s.append(si)
    if 'S' in si:
        st = (i, si.index('S'))
    if 'G' in si:
        gl = (i, si.index('G'))

vst = [[False] * w for i in range(h)]
vst[st[0]][st[1]] = True
prv = [(st, 0), (st, 1)]
nxt = []
trn = 0
while prv != []:
    for co in prv:
        if co[1] == 0:
            for dj in [-1, 1]:
                nx = (co[0][0], co[0][1] + dj)
                if 0 <= nx[1] < w and not vst[nx[0]][nx[1]]:
                    if s[nx[0]][nx[1]] == 'G':
                        print(trn + 1)
                        quit()
                    if s[nx[0]][nx[1]] == '.':
                        nxt.append((nx, 1))
        else:
            for di in [-1, 1]:
                nx = (co[0][0] + di, co[0][1])
                if 0 <= nx[0] < h and not vst[nx[0]][nx[1]]:
                    if s[nx[0]][nx[1]] == 'G':
                        print(trn + 1)
                        quit()
                    if s[nx[0]][nx[1]] == '.':
                        nxt.append((nx, 0))
    for nx in nxt:
        vst[nx[0][0]][nx[0][1]] = True
    prv = nxt
    nxt = []
    trn += 1

print(-1)

Submission Info

Judge Result