#include<iostream>

#include<cstring>

#include<algorithm>

#include<queue>

#include<map>

#include<stack>

#include<cmath>

#include<vector>

#include<set>

#include<cstdio>

#include<string>

#include<deque>

using namespace std;

typedef long long LL;

#define eps 1e-8

#define INF 0x3f3f3f3f

#define maxn 3000005

/*struct point{

    int u,w;

};

bool operator <(const point &s1,const point &s2)

{

    if(s1.w!=s2.w)

    return s1.w>s2.w;

    else

    return s1.u>s2.u;

}*/

int n,m,k,t;

double limit,dp[maxn];

int value[];

double A,B,C;//用来记录一张发票里面ABC的总价格

bool jug(char c,double cost)//判断这张发票是否可以报销

{

    if(c=='A')

    A+=cost;

    else if(c=='B')

    B+=cost;

    else if(c=='C')

    C+=cost;

    else

    return false;

    if(cost>||A>||B>||C>)

    return false;

    return true;

}

int main()

{

    while(scanf("%lf%d",&limit,&n))

    {

        limit*=;

        if(n==)

        break;

        fill(value,value+,INF);

        int num;

        double sum,cost;

        char c;

        for(int i=;i<=n;i++)

        {

            scanf("%d",&num);

            sum=;

            A=,B=,C=;

            while(num--)

            {

                getchar();

                scanf("%c:%lf",&c,&cost);

                if(sum!=INF&&jug(c,cost))

                {

                    sum+=cost;

                    if(sum>)

                    sum=INF;//如果不行就设为无穷大，表示无法报销

                }

                else

                sum=INF;

            }

            if(sum!=INF)

            {

                value[i]=sum*;

            }

        }

        memset(dp,,sizeof(dp));

        for(int i=;i<=n;i++)//一维的01背包

        {

            if(value[i]==INF)

            continue;

            for(int j=(int)limit;j>=value[i];j--)

            dp[j]=max(dp[j],dp[j-value[i]]+value[i]);

        }

        printf("%.2lf\n",dp[(int)limit]/);

    }

    return ;

}