Buggy python submission (verdict: Runtime Error):
def main():
    while True:
        n = int(input().strip())

        if n == 0:
            break

        phrases = []
        for _ in range(n):
            word = input().strip()
            phrases.append(word)

        PHRASE_LEN = [5,7,5,7,7]
        found_flag = False

        for i in range(n):
            acc_len = 0
            phrase_idx = 0
            for j in range(i, n):
                acc_len += len(phrases[j])

                if acc_len == PHRASE_LEN[phrase_idx]:
                    if phrase_idx == (len(PHRASE_LEN)-1):
                        found_flag = True
                        break

                    acc_len = 0
                    phrase_idx += 1
                elif acc_len > PHRASE_LEN[phrase_idx]:
                    break

            if found_flag:
                print(i+1)
                break

if __name__ == "__main__":
    main()
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~                       


Fixed submission:
def main():
    while True:
        n = int(input().strip())

        if n == 0:
            break

        phrases = []
        for _ in range(n):
            word = input().strip()
            phrases.append(word)

        PHRASE_LEN = [5,7,5,7,7]
        found_flag = False

        for i in range(n):
            acc_len = 0
            phrase_idx = 0
            for j in range(i, n):
                acc_len += len(phrases[j])

                if acc_len == PHRASE_LEN[phrase_idx]:
                    if phrase_idx == (len(PHRASE_LEN)-1):
                        found_flag = True
                        break

                    acc_len = 0
                    phrase_idx += 1
                elif acc_len > PHRASE_LEN[phrase_idx]:
                    break

            if found_flag:
                print(i+1)
                break

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Runtime Error):
def main():
    while True:
        n = int(input().strip())

        if n == 0:
            break

        phrases = []
        for _ in range(n):
            word = input().strip()
            phrases.append(word)

        PHRASE_LEN = [5,7,5,7,7]
        found_flag = False

        for i in range(n):
            acc_len = 0
            phrase_idx = 0
            for j in range(i, n):
                acc_len += len(phrases[j])

                if acc_len == PHRASE_LEN[phrase_idx]:
                    if phrase_idx == (len(PHRASE_LEN)-1):
                        found_flag = True
                        break

                    acc_len = 0
                    phrase_idx += 1
                elif acc_len > PHRASE_LEN[phrase_idx]:
                    break

            if found_flag:
                print(i+1)
                break

if __name__ == "__main__":
    main()
~                                                                                                                                                                                                                   
~                                                                                                                                                                                                                   
~                       


Fixed submission:
def main():
    while True:
        n = int(input().strip())

        if n == 0:
            break

        phrases = []
        for _ in range(n):
            word = input().strip()
            phrases.append(word)

        PHRASE_LEN = [5,7,5,7,7]
        found_flag = False

        for i in range(n):
            acc_len = 0
            phrase_idx = 0
            for j in range(i, n):
                acc_len += len(phrases[j])

                if acc_len == PHRASE_LEN[phrase_idx]:
                    if phrase_idx == (len(PHRASE_LEN)-1):
                        found_flag = True
                        break

                    acc_len = 0
                    phrase_idx += 1
                elif acc_len > PHRASE_LEN[phrase_idx]:
                    break

            if found_flag:
                print(i+1)
                break

if __name__ == "__main__":
    main()