样例全对，提交全WA，最后一个subtask全RE。

#include<bits/stdc++.h>
#include<iostream>
using namespace std;
typedef long long ll;
struct node{
	ll aa,b;
}a[10001];
ll n,p,x,y,ans,t,s;
bool cmp(node x,node y){
	return x.aa<y.aa;
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>p;
	for(ll i=1;i<=n;i++){
		cin>>x>>y;
		if(i==p)ans=x;
		else{
			if(x-y>=0){
				a[++t].aa=y;
				a[t].b=x-y;
			}
		}
	}
	sort(a+1,a+t+1,cmp);
	for(ll i=1;i<=t;i++){
		cout<<a[i].aa<<" "<<a[i].b<<'\n';
		if(ans>=a[i].aa){
			ans+=a[i].b;
			s++;
		}
		else{
			break;
		}
	}
	cout<<ans<<'\n'<<s;
	return 0;
}