BigSegment.java

/*	https://codeforces.com/contest/242/problem/B
	tag: #implementation #sorting
	assume each column as a min values array and max values array respectively.
	find the minimum value and maximum value.
	and find out if having an index i that
	min-array[i] = min-value, max-array[i] = max-value
*/

import java.util.Scanner;

public class BigSegment {

  static int findIndexBigSegment() {

    Scanner scanner = new Scanner(System.in);
    int length = scanner.nextInt();
    int minArr[] = new int[length];
    int maxArr[] = new int[length];

    minArr[0] = scanner.nextInt();
    maxArr[0] = scanner.nextInt();
    int minValue = minArr[0];
    int maxValue = maxArr[0];

    for (int i = 1; i < length; i++) {
      minArr[i] = scanner.nextInt();
      if (minArr[i] < minValue) {
        minValue = minArr[i];
      }
      maxArr[i] = scanner.nextInt();
      if (maxArr[i] > maxValue) {
        maxValue = maxArr[i];
      }
    }

    for (int i = 0; i < length; i++) {
      if (minArr[i] == minValue && maxArr[i] == maxValue) return i + 1;
    }

    return -1;
  }

  public static void main(String args[]) {
    System.out.println(findIndexBigSegment());
  }
}