문제
풀이
#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
void solve(void) {
int n, k; cin >> n >> k;
vector<int> a(n), b(n);
for (int i=0; i<n; i++) cin >> a[i] >> b[i];
vector<int> v(n);
for (int i=0; i<n; i++) {
v[i] = b[i] - a[i];
}
sort(v.begin(), v.end());
cout << max(0, v[k-1]);
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}