Why 80 WA on #2 #10

#include<bits/stdc++.h>
using namespace std;

struct kkksc03 {
	int num, scr;
};
vector<kkksc03> kkksc03s;

bool cmp(kkksc03 a, kkksc03 b) {
	if (a.scr != b.scr)
		return a.scr > b.scr;
	else
		return a.num < b.num;
}

int main() {
	int n, m;
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		kkksc03 _1kkksc03;
		cin >> _1kkksc03.num >> _1kkksc03.scr;
		kkksc03s.push_back(_1kkksc03);
	}
	sort(kkksc03s.begin(), kkksc03s.end(), cmp);
	int ans = 0;
	stringstream strstr;
	for (; kkksc03s[ans].scr >= kkksc03s[m * 3 / 2].scr && ans < n; ans++)
		strstr << kkksc03s[ans].num << ' ' << kkksc03s[ans].scr << endl;
	cout << kkksc03s[m * 3 / 2].scr << ' ' << ans << endl << strstr.str();
}