Buggy python submission (verdict: Runtime Error):
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]　　　　　　　　#倒せたら０にする。最後引いた時に残るように。
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)

Fixed submission:
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):                  #倒せたら０にする。最後に引いたら残るように
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)

Buggy python submission (verdict: Runtime Error):
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]　　　　　　　　#倒せたら０にする。最後引いた時に残るように。
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)

Fixed submission:
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):                  #倒せたら０にする。最後に引いたら残るように
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)

Buggy python submission (verdict: Runtime Error):
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]$　　　　　　　　#倒せたら０にする。最後引いた時に残るように。
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)

Fixed submission:
N = int(input())
A = [int(_) for _ in input().split()]
B = [int(_) for _ in input().split()]
def_Bsum = sum(B)
 
for i in range(N+1):
    if(i==0):                  #倒せたら０にする。最後に引いたら残るように
        if (A[i] < B[i]):
            B[i] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i]
            B[i] = 0
 
    if(0<i<N):
        if(A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
            if (A[i] < B[i]):
                B[i] -= A[i]
                A[i] = 0
            else:
                A[i] -= B[i]
                B[i] = 0
 
    if(i==N):
        if (A[i] < B[i-1]):
            B[i-1] -= A[i]
            A[i] = 0
        else:
            A[i] -= B[i-1]
            B[i-1] = 0
 
 
ans = def_Bsum - sum(B)

print(ans)