"""R607：从已运行合成评分格识别四邻连通区域；缺失不是零。"""
from collections import deque

FAST = [2, 3, 4, 5]
SLOW = [10, 12, 14, 16]
SCORES = [[6, 7, -2, 1], [7, 8, -1, 2],
          [-3, -2, None, 1], [1, 0, 2, 25]]


def components(scores, threshold=5):
    good = {(i, j) for i, row in enumerate(scores)
            for j, score in enumerate(row) if score is not None and score >= threshold}
    found = []
    while good:
        start = min(good)
        good.remove(start)
        queue, region = deque([start]), [start]
        while queue:
            i, j = queue.popleft()
            for candidate in [(i-1, j), (i+1, j), (i, j-1), (i, j+1)]:
                if candidate in good:
                    good.remove(candidate)
                    queue.append(candidate)
                    region.append(candidate)
        found.append(sorted(region))
    return found


def representative(region, scores):
    return min(region, key=lambda p: (
        sum(abs(p[0]-q[0]) + abs(p[1]-q[1]) for q in region),
        -scores[p[0]][p[1]], p))


def run():
    regions = components(SCORES)
    cells = sum(len(row) for row in SCORES)
    observed = sum(value is not None for row in SCORES for value in row)
    acceptable = sum(value is not None and value >= 5 for row in SCORES for value in row)
    assert sum(map(len, regions)) == acceptable
    eligible = [region for region in regions if len(region) >= 4]
    assert [len(region) for region in regions] == [4, 1]
    assert len(eligible) == 1
    point = representative(eligible[0], SCORES)
    assert point == (1, 1)
    assert SCORES[3][3] == 25 and (3, 3) not in eligible[0]
    missing_bridge = components([[6, None, 7]])
    assert [len(region) for region in missing_bridge] == [1, 1]
    print(f"cells={cells} observed={observed} missing={cells-observed} acceptable={acceptable}")
    print("component_sizes=" + str([len(region) for region in regions]))
    print(f"selected_fast={FAST[point[0]]} selected_slow={SLOW[point[1]]} score={SCORES[point[0]][point[1]]}")
    print("isolated_peak=25 rejected; missing_bridge_sizes=[1, 1]")


if __name__ == "__main__":
    run()