Buggy python submission (verdict: Runtime Error):
# Fast IO (be careful about bytestring)

# import os,io
# input=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline


H,W,M = map(int,input().split())
targetList = []
rowCount = [0] * H
columnCount = [0] * W
for _ in range(M):
    p,q = map(int,input().split())
    targetList.append((p-1,q-1))
    rowCount[p-1] += 1
    columnCount[q-1] += 1
rowCountLabelled = []
columnCountLabelled = []
for i in range(H):
    rowCountLabelled.append((rowCount[i],i))
for i in range(W):
    columnCountLabelled.append((columnCount[i],i))
rowCountLabelled.sort(reverse = True)
columnCountLabelled.sort(reverse = True)
targetList.sort()
maxi = rowCountLabelled[0][0] + columnCountLabelled[0][0]
isMaxAchievable = False
for elem1 in rowCountLabelled:
    if elem1[0] != rowCountLabelled[0][0]:
        break
    for elem2 in columnCountLabelled:
        if elem2[0] != columnCountLabelled[0][0]:
            break
        target = (elem1[1],elem2[1])
        l = 0
        r = len(targetList)
        while l < r:
            m = (l + r) // 2
            if target == targetList[m]:
                l = m
                r = m
                break
            elif target < targetList[m]:
                r = m-1
            elif target > targetList[m]:
                l = m + 1
        if (l >= len(targetList) or target != targetList[l]) and target != targetList[r]:
            isMaxAchievable = True
            break
    if isMaxAchievable:
        break
if isMaxAchievable:
    print(maxi)
else:
    print(maxi - 1)


Fixed submission:
# Fast IO (be careful about bytestring)

# import os,io
# input=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline


H,W,M = map(int,input().split())
targetList = []
rowCount = [0] * H
columnCount = [0] * W
for _ in range(M):
    p,q = map(int,input().split())
    targetList.append((p-1,q-1))
    rowCount[p-1] += 1
    columnCount[q-1] += 1
rowCountLabelled = []
columnCountLabelled = []
for i in range(H):
    rowCountLabelled.append((rowCount[i],i))
for i in range(W):
    columnCountLabelled.append((columnCount[i],i))
rowCountLabelled.sort(reverse = True)
columnCountLabelled.sort(reverse = True)
targetList.sort()
maxi = rowCountLabelled[0][0] + columnCountLabelled[0][0]
isMaxAchievable = False
for elem1 in rowCountLabelled:
    if elem1[0] != rowCountLabelled[0][0]:
        break
    for elem2 in columnCountLabelled:
        if elem2[0] != columnCountLabelled[0][0]:
            break
        target = (elem1[1],elem2[1])
        l = 0
        r = len(targetList) - 1
        while l < r:
            m = (l + r) // 2
            if target == targetList[m]:
                l = m
                r = m
                break
            elif target < targetList[m]:
                r = m-1
            elif target > targetList[m]:
                l = m + 1
        if (l >= len(targetList) or target != targetList[l]) and target != targetList[r]:
            isMaxAchievable = True
            break
    if isMaxAchievable:
        break
if isMaxAchievable:
    print(maxi)
else:
    print(maxi - 1)

Buggy python submission (verdict: Runtime Error):
# Fast IO (be careful about bytestring)

# import os,io
# input=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline


H,W,M = map(int,input().split())
targetList = []
rowCount = [0] * H
columnCount = [0] * W
for _ in range(M):
    p,q = map(int,input().split())
    targetList.append((p-1,q-1))
    rowCount[p-1] += 1
    columnCount[q-1] += 1
rowCountLabelled = []
columnCountLabelled = []
for i in range(H):
    rowCountLabelled.append((rowCount[i],i))
for i in range(W):
    columnCountLabelled.append((columnCount[i],i))
rowCountLabelled.sort(reverse = True)
columnCountLabelled.sort(reverse = True)
targetList.sort()
maxi = rowCountLabelled[0][0] + columnCountLabelled[0][0]
isMaxAchievable = False
for elem1 in rowCountLabelled:
    if elem1[0] != rowCountLabelled[0][0]:
        break
    for elem2 in columnCountLabelled:
        if elem2[0] != columnCountLabelled[0][0]:
            break
        target = (elem1[1],elem2[1])
        l = 0
        r = len(targetList)
        while l < r:
            m = (l + r) // 2
            if target == targetList[m]:
                l = m
                r = m
                break
            elif target < targetList[m]:
                r = m-1
            elif target > targetList[m]:
                l = m + 1
        if target != targetList[l] and target != targetList[r]:
            isMaxAchievable = True
            break
    if isMaxAchievable:
        break
if isMaxAchievable:
    print(maxi)
else:
    print(maxi - 1)


Fixed submission:
# Fast IO (be careful about bytestring)

# import os,io
# input=io.BytesIO(os.read(0,os.fstat(0).st_size)).readline


H,W,M = map(int,input().split())
targetList = []
rowCount = [0] * H
columnCount = [0] * W
for _ in range(M):
    p,q = map(int,input().split())
    targetList.append((p-1,q-1))
    rowCount[p-1] += 1
    columnCount[q-1] += 1
rowCountLabelled = []
columnCountLabelled = []
for i in range(H):
    rowCountLabelled.append((rowCount[i],i))
for i in range(W):
    columnCountLabelled.append((columnCount[i],i))
rowCountLabelled.sort(reverse = True)
columnCountLabelled.sort(reverse = True)
targetList.sort()
maxi = rowCountLabelled[0][0] + columnCountLabelled[0][0]
isMaxAchievable = False
for elem1 in rowCountLabelled:
    if elem1[0] != rowCountLabelled[0][0]:
        break
    for elem2 in columnCountLabelled:
        if elem2[0] != columnCountLabelled[0][0]:
            break
        target = (elem1[1],elem2[1])
        l = 0
        r = len(targetList) - 1
        while l < r:
            m = (l + r) // 2
            if target == targetList[m]:
                l = m
                r = m
                break
            elif target < targetList[m]:
                r = m-1
            elif target > targetList[m]:
                l = m + 1
        if (l >= len(targetList) or target != targetList[l]) and target != targetList[r]:
            isMaxAchievable = True
            break
    if isMaxAchievable:
        break
if isMaxAchievable:
    print(maxi)
else:
    print(maxi - 1)