Problem:
Score : 200 points

Problem Statement

You are visiting a large electronics store to buy a refrigerator and a microwave.

The store sells A kinds of refrigerators and B kinds of microwaves. The i-th refrigerator ( 1 \le i \le A ) is sold at a_i yen (the currency of Japan), and the j-th microwave ( 1 \le j \le B ) is sold at b_j yen.

You have M discount tickets. With the i-th ticket ( 1 \le i \le M ), you can get a discount of c_i yen from the total price when buying the x_i-th refrigerator and the y_i-th microwave together. Only one ticket can be used at a time.

You are planning to buy one refrigerator and one microwave. Find the minimum amount of money required.

Constraints

All values in input are integers.

1 \le A \le 10^5

1 \le B \le 10^5

1 \le M \le 10^5

1 \le a_i , b_i , c_i \le 10^5

1 \le x_i \le A

1 \le y_i \le B

c_i \le a_{x_i} + b_{y_i}

Input

Input is given from Standard Input in the following format:

A B M
a_1 a_2 ... a_A
b_1 b_2 ... b_B
x_1 y_1 c_1
\vdots
x_M y_M c_M

Output

Print the answer.

Sample Input 1

2 3 1
3 3
3 3 3
1 2 1

Sample Output 1

5

With the ticket, you can get the 1-st refrigerator and the 2-nd microwave for 3+3-1=5 yen.

Sample Input 2

1 1 2
10
10
1 1 5
1 1 10

Sample Output 2

10

Note that you cannot use more than one ticket at a time.

Sample Input 3

2 2 1
3 5
3 5
2 2 2

Sample Output 3

6

You can get the 1-st refrigerator and the 1-st microwave for 6 yen, which is the minimum amount to pay in this case.
Note that using a ticket is optional.

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

A,B, M = map(int,input().split())

A_list = list(map(int,input().split()))
B_list = list(map(int,input().split()))

x_list = []
y_list = []
c_list = []

#print(A,B,M)
#print(A_list)
#print(B_list)

min = 10000000
for i in range(M):
    x,y,c= list(map(int,input().split()))
    #print(x,y,c)
    try:
        index = x_list.index(x-1)
        if c_list[index] < c:
            c_list[index] = c
    except ValueError:
        x_list.append(x-1)
        y_list.append(y-1)
        c_list.append(c)

#print(x_list)
#print(y_list)
#print(c_list)

if A >= B:
    for j in range(B):
        #print(j)
        try:
            index = x_list.index(j)
            sum = A_list[j] + B_list[j] - c_list[index]
        except ValueError:
            #print(ValueError)
            sum = A_list[j] + B_list[j]
        #print(sum)
        if sum < min:
            min = sum


else:
    for k in range(A):
        #print(k)
        try:
            index = x_list.index(k)
            sum = A_list[k] + B_list[k] - c_list[index]
        except ValueError:
            #print(ValueError)
            sum = A_list[k] + B_list[k]
        #print(sum)
        if sum < min:
            min = sum


    

print(min)