import sys

def main():
    sys.setrecursionlimit(1 << 25)
    N, M = map(int, sys.stdin.readline().split())
    A = list(map(int, sys.stdin.readline().split()))
    B = list(map(int, sys.stdin.readline().split()))
    
    prefixA = [0] * (N + 1)
    for i in range(1, N+1):
        prefixA[i] = prefixA[i-1] + A[i-1]
    
    prefixB = [0] * (M + 1)
    for i in range(1, M+1):
        prefixB[i] = prefixB[i-1] + B[i-1]
    
    INF = float('inf')
    
    dp = [[INF] * (M+1) for _ in range(N+1)]
    dp[0][0] = 0
    
    for i in range(N+1):
        for j in range(M+1):
            if i == 0 and j == 0:
                dp[i][j] = 0
                continue
            if dp[i][j] == INF:
                continue
            # Try adding an operation to merge A
            if i > 1:
                for k in range(1, i):
                    new_sum = prefixA[i] - prefixA[k]
                    cost = 1 + abs(new_sum - (prefixB[j] - prefixB[j]))
                    if dp[i][j] + cost < dp[k][j]:
                        dp[k][j] = dp[i][j] + cost
            # Similarly, try to split or other operations
            # This is a placeholder for the actual DP transitions
            
    print(dp[N][M])
    
if __name__ == "__main__":
    main()