Problem: There are N(N+1)/2 dots arranged to form an equilateral triangle whose sides consist of N dots, as shown below. The j-th dot from the left in the i-th row from the top is denoted by (i, j) (1 \leq i \leq N, 1 \leq j \leq i). Also, we will call (i+1, j) immediately lower-left to (i, j), and (i+1, j+1) immediately lower-right to (i, j).

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Takahashi is drawing M polygonal lines L_1, L_2, ..., L_M by connecting these dots. Each L_i starts at (1, 1), and visits the dot that is immediately lower-left or lower-right to the current dots N-1 times. More formally, there exist X_{i,1}, ..., X_{i,N} such that:

* L_i connects the N points (1, X_{i,1}), (2, X_{i,2}), ..., (N, X_{i,N}), in this order.
* For each j=1, 2, ..., N-1, either X_{i,j+1} = X_{i,j} or X_{i,j+1} = X_{i,j}+1 holds.



Takahashi would like to draw these lines so that no part of L_{i+1} is to the left of L_{i}. That is, for each j=1, 2, ..., N, X_{1,j} \leq X_{2,j} \leq ... \leq X_{M,j} must hold.

Additionally, there are K conditions on the shape of the lines that must be followed. The i-th condition is denoted by (A_i, B_i, C_i), which means:

* If C_i=0, L_{A_i} must visit the immediately lower-left dot for the B_i-th move.
* If C_i=1, L_{A_i} must visit the immediately lower-right dot for the B_i-th move.



That is, X_{A_i, {B_i}+1} = X_{A_i, B_i} + C_i must hold.

In how many ways can Takahashi draw M polygonal lines? Find the count modulo 1000000007.

Constraints

* 1 \leq N \leq 20
* 1 \leq M \leq 20
* 0 \leq K \leq (N-1)M
* 1 \leq A_i \leq M
* 1 \leq B_i \leq N-1
* C_i = 0 or 1
* No pair appears more than once as (A_i, B_i).

Input

Input is given from Standard Input in the following format:


N M K
A_1 B_1 C_1
A_2 B_2 C_2
:
A_K B_K C_K


Output

Print the number of ways for Takahashi to draw M polygonal lines, modulo 1000000007.

Examples

Input

3 2 1
1 2 0


Output

6


Input

3 2 2
1 1 1
2 1 0


Output

0


Input

5 4 2
1 3 1
4 2 0


Output

172


Input

20 20 0


Output

881396682

Solution (in CPP):

Solution:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <iostream>
#include <functional>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <bitset>

using namespace std;
typedef pair<int, int> Pi;
typedef long long ll;
#define pii Pi
#define pll PL
#define Fi first
#define Se second
#define pb(x) push_back(x)
//#define sz(x) ((int)(x).size())
#define rep(i, n) for(int i=0;i<n;i++)
#define all(x) (x).begin(), (x).end()
typedef tuple<int, int, int> t3;
typedef pair<ll, ll> pll;
typedef long double ldouble;
typedef pair<double, double> pdd;

const double PI = acos(-1);
const double EPS = 1e-9;

const int MX = 1<<20;
const int MM = 1000000007;

int T[MX];
int msk[MX], val[MX];
int N, M, K;

int nxt(int i, int v){
	return ((i + (1<<v)) | (i^1<<v)) & ((1<<N)-1);
}

int main()
{
	scanf("%d%d%d", &N, &M, &K); N--;
	for(int i = 1; i <= K; i++){
		int a, b, c;
		scanf("%d%d%d", &a, &b, &c);
		msk[a] |= 1<<b-1;
		val[a] |= c<<b-1;
	}

	for(int i = 0; i < 1<<N; i++){
		if( val[1] == (msk[1]&i)) T[i] = 1;
	}
	for(int t = 2; t <= M; t++){
		for(int v = N-1; v >= 0; v--){
			for(int i = 0; i < 1<<N; i++){
				if( i&1<<v ) T[i] = (T[i] + T[nxt(i, v)]) % MM;
			}
		}
		
		for(int i = 0; i < 1<<N; i++){
			if( val[t] != (msk[t]&i) ) T[i] = 0;
		}
	}
	int ans = 0;
	for(int i = 0; i < 1<<N; i++) ans = (ans + T[i]) % MM;
	printf("%d\n", ans);
}