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 C (GCC 5.4.1) (judge verdict: Accepted)

/*  AUTHOR: AKASH JAIN
*   EMAIL:  akash19jain@gmail.com
*   ID:     akash19jain  
*   DATE:   08-03-2020 17:39:15
*/


// #include<algorithm>
// #include <bits/stdc++.h>
// using namespace std;
 
#include<stdio.h>
#include<math.h>
#include<string.h>
#include<stdlib.h>
#include<stdbool.h>
#include<ctype.h>
#define SC1(x)          scanf("%lld",&x)
#define SC2(x,y)        scanf("%lld%lld",&x,&y)
#define SC3(x,y,z)      scanf("%lld%lld%lld",&x,&y,&z)
#define SCS(x)          scanf("\n%s", x)
#define SCA(a,n)        for(long long i=0;i<n;i++)    scanf("%lld",&a[i]);
#define PF1(x)          printf("%lld\n",x)
#define PF2(x,y)        printf("%lld %lld\n",x,y)
#define PF3(x,y,z)      printf("%lld %lld %lld\n",x,y,z)
#define PFA(a,n)        for(long long i=0;i<n;i++)    printf("%lld ",a[i]); printf("\n");
#define PFN             printf("\n")
#define PFS(x)          printf("%s\n",x)
#define REP(i,n)        for(long long i=0;i<(n);++i)
#define FOR(i,a,b)      for(long long i=(a);i<=(b);++i)
#define FORD(i,a,b)     for(long long i=(a);i>=(b);--i)
#define WHILE(n)        while(n--)
#define MEM(a, b)       memset(a, (b), sizeof(a))
#define ITOC(c)         ((char)(((ll)'0')+c))
#define MID(s,e)        (s+(e-s)/2)
#define SZ(a)           strlen(a)          
#define PI              3.1415926535897932384626433832795
#define DEB(x)          printf("The value of \"%s\" is: %d\n",#x,x)
#define CASES           ll t;SC1(t);while(t--)
#define ABS(a)          ((a>0)?a:-(a))
#define SWAP(a,b)       ll z=a;a=b;b=z
#define SWAPC(a,b)      char z=a;a=b;b=z
#define FLSH            fflush(stdout)
typedef long long ll;
typedef unsigned long long ull;
const ll INF = 1<<29;
const ll MOD = 1000000007;
const ll FMOD = 998244353;
const ll MAX = 10000000005;
const ll MIN = -10000000005;
#define FILEIO(name) \  freopen(name".in", "r", stdin); \   freopen(name".out", "w", stdout);
int cmp(const void * a,const void * b);
long long maxv(long long a,long long b);
long long minv(long long a,long long b);
long long gcd(long long u,long long v);
long long digits(long long n);
bool ispoweroftwo(long long n);
bool isvowel(char x);
ll chartoint(char ch);
ll CEIL(ll x,ll y);
ll FLOOR(ll x,ll y);


int main()
{
    ll a,b,m;
    SC3(a,b,m);
    ll ref[a],mic[b];
    SCA(ref,a);
    SCA(mic,b);
    ll ma=MAX,mb=MAX;
    REP(i,a)
    {
        if(ref[i]<ma)
            ma=ref[i];
    }
    REP(i,b)
    {
        if(mic[i]<mb)
            mb=mic[i];
    }
    ll min=ma+mb;
    while(m--)
    {
        ll x,y,z;
        SC3(x,y,z);
        ll sum=ref[x-1]+mic[y-1]-z;
        if(sum<min)
            min=sum;
    }
    PF1(min);
    return 0;
}
 
 
//qsort(arr,n,sizeof(arr[0]),cmp);
int cmp (const void * a, const void * b)
{
    if( *(ll*)a - *(ll*)b < 0 ) return -1;
    if( *(ll*)a - *(ll*)b > 0 ) return 1;
        return 0;
}
long long maxv(long long a,long long b)
{
    if(a>b) return a;
        return b;
}
long long minv(long long a,long long b)
{
    if(a<b) return a;
        return b;
}
long long gcd(long long u,long long v)
{
    if (v == 0) return u; 
       return gcd(v, u%v);
}
long long digits(long long n)    //to calculate no of digits in a number
{
    return floor(log10(n))+1;
}
bool ispoweroftwo(long long x)
{
    return x && (!(x&(x-1)));
}
bool isvowel(char x)
{
    return(x=='a' || x== 'e' ||x=='i' || x== 'o' || x=='u' );
}
ll chartoint(char ch)
{
    if(ch>='A' && ch<='Z') return(ch-'A');
    else if(ch>='0' && ch<='9') return (ch-'0');
    else if(ch>='a' && ch<='z') return (ch-'a');
    else return 0;
}
ll CEIL(ll x,ll y)
{
    if(x%y==0) return(x/y);
    else return(x/y +1);
}
 
ll FLOOR(ll x,ll y)
{
    if(x%y==0) return(x/y);
    else return(x/y -1);
}