#include <iostream>
#include <algorithm>

using namespace std;

typedef struct Cai
{
	int info;
	int cost;
}Cai;

bool Cmpare(const Cai &a,const Cai &b){
	return a.info > b.info;//升序
}

int main(int argc, char const *argv[])
{
	int C,N,Info,Cost;
	Cai A[100];
	while(cin>>C>>N){
		Info=Cost=0;
		for (int i = 0; i < N; ++i)
		{
			cin>>A[i].cost>>A[i].info;
		}
		sort(A,A+N,Cmpare);
		for (int i = 0; i < N; ++i)
		{
			if (Cost+A[i].cost<=90)
			{
				Info+=A[i].info;
			    Cost+=A[i].cost;
			}else{
				break;
			}
		}
		cout<<Info<<endl;
	}

	return 0;
}