Problem p03263 (python)

Fixed submission:
h, w = map(int, input().split())
lst = [list(map(int, input().split())) for _ in range(h)]

count = 0
ans = []
for i in range(0, h-1, 2):
    for j in range(w):
        if lst[i][j] % 2 == 1:
            count += 1
            if j == w-1:
                lst[i+1][j] += 1
                ans.append((i+1, j+1, i+2, j+1))
            else:
                lst[i][j+1] += 1
                ans.append((i+1, j+1, i+1, j+2))
    for j in reversed(range(w)):
        if lst[i+1][j] % 2 == 1:
            if j == 0 and i+1 == h-1:
                pass
            elif j == 0:
                lst[i+2][j] += 1
                ans.append((i+2, j+1, i+3, j+1))
                count += 1
            else:
                lst[i+1][j-1] += 1
                ans.append((i+2, j+1, i+2, j))
                count += 1
if h % 2 == 1:
    for j in range(w):
        if lst[-1][j] % 2 == 1:
            if j == w-1:
                pass
            else:
                lst[-1][j+1] += 1
                ans.append((h, j+1, h, j+2))
                count += 1
                
print(count)
for a,b,c,d in ans:
    print(a,b,c,d)

Buggy submission (verdict: Runtime Error):
h, w = map(int, input().split())
lst = [list(map(int, input().split())) for _ in range(h)]

count = 0
ans = []
for i in range(0, h-1, 2):
    for j in range(w):
        if lst[i][j] % 2 == 1:
            count += 1
            if j == w-1:
                lst[i+1][j] += 1
                ans.append((i+1, j+1, i+2, j+1))
            else:
                lst[i][j+1] += 1
                ans.append((i+1, j+1, i+1, j+2))
    for j in reversed(range(w)):
        if lst[i+1][j] % 2 == 1:
            if j == 0 and i == h-1:
                pass
            elif j == 0:
                lst[i+2][j] += 1
                ans.append((i+2, j+1, i+3, j+1))
                count += 1
            else:
                lst[i+1][j-1] += 1
                ans.append((i+2, j+1, i+2, j))
                count += 1
if h % 2 == 1:
    for j in range(w):
        if lst[-1][j] % 2 == 1:
            if j == w-1:
                pass
            else:
                lst[-1][j+1] += 1
                ans.append((h, j+1, h, j+2))
                count += 1
                
print(count)
for a,b,c,d in ans:
    print(a,b,c,d)

Buggy submission (verdict: Runtime Error):
h, w = map(int, input().split())
lst = [list(map(int, input().split())) for _ in range(h)]

count = 0
ans = []
for i in range(0, h-1, 2):
    for j in range(w):
        if lst[i][j] % 2 == 1:
            count += 1
            if j == w-1:
                lst[i+i][j] += 1
                ans.append((i+1, j+1, i+2, j+1))
            else:
                lst[i][j+1] += 1
                ans.append((i+1, j+1, i+1, j+2))
    for j in reversed(range(w)):
        if lst[i+1][j] % 2 == 1:
            if j == 0 and i == h-1:
                pass
            elif j == 0:
                lst[i+2][j] += 1
                ans.append((i+2, j+1, i+3, j+1))
                count += 1
            else:
                lst[i][j-1] += 1
                ans.append((i+2, j+1, i+2, j))
                count += 1
if h % 2 == 1:
    for j in range(w):
        if lst[-1][j] % 2 == 1:
            if j == w-1:
                pass
            else:
                lst[i][j+1] += 1
                ans.append((i+1, j+1, i+1, j+2))
                count += 1
                
print(count)
for a,b,c,d in ans:
    print(a,b,c,d)