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 *       notice, this list of conditions and the following disclaimer.
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 *       notice, this list of conditions and the following disclaimer in the
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 *       to endorse or promote products derived from this software without 
 *       specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY XEHOTH AND CONTRIBUTORS "AS IS" AND ANY
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 ******************************************************************************/
#include <bits/stdc++.h>
/**
 * 「AtCoder Beginner Contest 061」 13-05-2017
 * @author xehoth 
 */
namespace IO {

inline char read() {
    static const int IN_LEN = 1000000;
    static char buf[IN_LEN], *s, *t;
    s == t ? t = (s = buf) + fread(buf, 1, IN_LEN, stdin) : 0;
    return s == t ? -1 : *s++;
}

template<class T>
inline void read(T &x) {
    static char c;
    static bool iosig;
    for (c = read(), iosig = false; !isdigit(c); c = read()) {
        if (c == -1) return;
        c == '-' ? iosig = true : 0;
    }
    for (x = 0; isdigit(c); c = read())
        x = (x + (x << 2) << 1) + (c ^ '0');
    iosig ? x = -x : 0;
}

const int OUT_LEN = 1000000;

char obuf[OUT_LEN], *oh = obuf;

inline void print(char c) {
    oh == obuf + OUT_LEN ? (fwrite(obuf, 1, OUT_LEN, stdout), oh = obuf) : 0;
    *oh++ = c;
}

template<class T>
inline void print(T x) {
    static int buf[30], cnt;
    if (x == 0) {
        print('0');
    } else {
        for (cnt = 0; x; x /= 10) buf[++cnt] = x % 10 | 48;
        while (cnt) print((char)buf[cnt--]);
    }
}

inline void flush() {
    fwrite(obuf, 1, oh - obuf, stdout);
}
}

namespace Task {

const int MAXN = 100005;

struct Query {
    int a, b;

    inline bool operator<(const Query &n) const {
        return a < n.a || (a == n.a && b < n.b);
    }
} q[MAXN];

inline void solve() {
    using namespace IO;
    register int n;
    register long long k;
    read(n), read(k);
    for (register int i = 0; i < n; i++) {
        read(q[i].a), read(q[i].b);
    }
    std::sort(q, q + n);
    for (register int i = 0; i < n; i++) {
        if (k <= q[i].b) {
            print(q[i].a), print('\n');
            return;
        }
        k -= q[i].b;
    }
}
}

int main() {
#ifdef DBG
    freopen("in.in", "r", stdin);
#endif
    Task::solve();
    IO::flush();
    return 0;
}


Measured memory_bytes: 2048