'use strict';

let lines = require('fs').readFileSync('/dev/stdin', 'utf8').split('\n');

let N = +(lines[0].split(' ')[0]);
let K = +(lines[0].split(' ')[1]);
let ABs = lines.slice(1).map(line => line.split(' ').map(Number));

ABs = ABs.sort((x, y) => x[0] < y[0] ? -1 : x[0] > y[0] ? +1 : 0);

let ab;
while (K > 0) {
    ab = ABs.shift();
    K -= ab[1];
}

console.log(ab[0]);