#include<bits/stdc++.h> #define int long long using namespace std; const int INF=1e18; struct block{int w,s;}; void chmin(int&a,int b){if(a>b)a=b;} block B[1100]; int dp[1100][1100]; signed main(){ int N;cin>>N; for(int i=0;i<N;i++)cin>>B[i].w>>B[i].s; sort(B,B+N,[](block a,block b){return a.w+a.s<b.w+b.s;}); fill(dp[0],dp[N+1],INF); dp[0][0]=0; for(int i=0;i<N;i++){ for(int j=0;j<=N;j++)dp[i+1][j]=dp[i][j]; for(int j=0;j<N;j++){ if(dp[i][j]<=B[i].s)chmin(dp[i+1][j+1],dp[i][j]+B[i].w); } } for(int i=N;i>0;i--){ if(dp[N][i]<=INF/2)return cout<<i<<endl,0; } cout<<0<<endl; }