#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <cstdio>
#include <cstring>
#include <iterator>
#include <bitset>
#include <unordered_set>
#include <unordered_map>
#include <fstream>
#include <iomanip>
#include <cassert>
//#include <utility>
//#include <memory>
//#include <functional>
//#include <deque>
//#include <cctype>
//#include <ctime>
//#include <numeric>
//#include <list>
//#include <iomanip>

//#if __cplusplus >= 201103L
//#include <array>
//#include <tuple>
//#include <initializer_list>
//#include <forward_list>
//
//#define cauto const auto&
//#else

//#endif

using namespace std;


typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

typedef vector<int> vint;
typedef vector<vector<int> > vvint;
typedef vector<long long> vll, vLL;
typedef vector<vector<long long> > vvll, vvLL;

#define VV(T) vector<vector< T > >

template <class T>
void initvv(vector<vector<T> > &v, int a, int b, const T &t = T()){
    v.assign(a, vector<T>(b, t));
}

template <class F, class T>
void convert(const F &f, T &t){
    stringstream ss;
    ss << f;
    ss >> t;
}

#undef _P
#define _P(...) (void)printf(__VA_ARGS__)
#define reep(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n) reep((i),0,(n))
#define ALL(v) (v).begin(),(v).end()
#define PB push_back
#define F first
#define S second
#define mkp make_pair
#define RALL(v) (v).rbegin(),(v).rend()
#define DEBUG
#ifdef DEBUG
#define dump(x)  cout << #x << " = " << (x) << endl;
#define debug(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;
#else
#define dump(x) 
#define debug(x) 
#endif
#define LDcout(x,n) fixed<<setprecision(n)<<x

#define MOD 1000000007LL
#define EPS 1e-8
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
#define maxs(x,y) x=max(x,y)
#define mins(x,y) x=min(x,y)
double dp[70][20000];
void mainmain(){
    int x,y,z;
    while(cin>>x>>y>>z,x){
        vint v(x);
        rep(i,x) cin>>v[i];
        vector<pii> w(y+100,pii(-1,-1));
        rep(i,z){
            int n,e,a;
            cin>>n>>e>>a;
            // cout<<n<<" "<<e<<" "<<a<<endl;
            w[n]=pii(e,a);
        }
        rep(i,70) rep(j,20000) dp[i][j]=0;
        dp[0][10000]=1;
        rep(i,y){
            rep(j,20000){
                if(dp[i][j]==0) continue;
                // cout<<i<<" "<<j<<endl;
                rep(k,x){
                    int pos=i+v[k];
                    int coin=j;
                    if(w[pos].F==1){
                        pos+=w[pos].S;
                    }
                    else if(w[pos].F==2){
                        coin+=w[pos].S;
                    }
                    else if(w[pos].F==3){
                        coin-=w[pos].S;
                    }
                    maxs(coin,10000);
                    dp[pos][coin]+=dp[i][j]/(double)x;
                }
            }
        }
        double ans=0;
        reep(i,y,70){
            rep(j,20000){
                if(dp[i][j]==0) continue;
                // cout<<dp[i][j]<<" "<<j<<endl;
                ans+=dp[i][j]*(j-10000);
            }
        }
        // cout<<ans<<endl;
        cout<<(int)ans<<endl;
    }
}


signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
      cout<<fixed<<setprecision(20);
    mainmain();
}

Measured memory_bytes: 12144