hdu1203 I NEED A OFFER!

#include <fstream>
#include <iostream>
#include <string>
#include <complex>
#include <math.h>
#include <cstdlib>
#include <set>
#include <vector>
#include <map>
#include <queue>
#include <stdio.h>
#include <stack>
#include <algorithm>
#include <list>
#include <ctime>
#include <memory.h>
#include <ctime>
#include <assert.h>

#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define eps 1e-8
#define M_PI 3.141592653589793

typedef long long ll;
const ll mod=1000000007;
const int inf=99999999;
ll powmod(ll a,ll b) {ll res=1;a%=mod;for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}

using namespace std;
double dp[10010],p[10010];
int n,m,v[100010];

int main()
{
while(scanf("%d %d",&m,&n)){
if(n==0&&m==0) break;
for(int i=0;i<n;i++){
cin>>v[i]>>p[i];
p[i]=1-p[i];
}
for(int i=0;i<=m;i++) dp[i]=1.0;
for(int i=0;i<n;i++){
for(int j=m;j>=v[i];j--){
dp[j]=min(dp[j],dp[j-v[i]]*p[i]);
}
}
printf("%.1f%%\n",(1-dp[m])*100);
}
}