[CF572A]Arrays

A. Arrays
 

You are given two arrays A and B consisting of integers, sorted in non-decreasing order. Check whether it is possible to choose k numbers in array A and choose m numbers in array B so that any number chosen in the first array is strictly less than any number chosen in the second array.

Input

The first line contains two integers nA, nB (1 ≤ nA, nB ≤ 105), separated by a space — the sizes of arrays A and B, correspondingly.

The second line contains two integers k and m (1 ≤ k ≤ nA, 1 ≤ m ≤ nB), separated by a space.

The third line contains nA numbers a1, a2, ... anA ( - 109 ≤ a1 ≤ a2 ≤ ... ≤ anA ≤ 109), separated by spaces — elements of array A.

The fourth line contains nB integers b1, b2, ... bnB ( - 109 ≤ b1 ≤ b2 ≤ ... ≤ bnB ≤ 109), separated by spaces — elements of array B.

Output

Print "YES" (without the quotes), if you can choose k numbers in array A and m numbers in array B so that any number chosen in array A was strictly less than any number chosen in array B. Otherwise, print "NO" (without the quotes).

Sample test(s)
Input
3 3
2 1
1 2 3
3 4 5
Output
YES
Input
3 3
3 3
1 2 3
3 4 5
Output
NO
Input
5 2
3 1
1 1 1 1 1
2 2
Output
YES
Note

In the first sample test you can, for example, choose numbers 1 and 2 from array A and number 3 from array B (1 < 3 and 2 < 3).

In the second sample test the only way to choose k elements in the first array and m elements in the second one is to choose all numbers in both arrays, but then not all the numbers chosen in A will be less than all the numbers chosen in B: .

直接比较a的第k个和b的第nb-m+1个元素的大小。

 1 #include <cstdio>
 2 #include <cstdlib>
 3 #include <cstring>
 4 #include <algorithm>
 5 #include <iostream>
 6 #include <cmath>
 7 #include <queue>
 8 #include <map>
 9 #include <stack>
10 #include <list>
11 #include <vector>
12 #include <ctime>
13 
14 using namespace std;
15 
16 const int maxn = 100010;
17 
18 int a[maxn];
19 int b[maxn];
20 int k, m;
21 int na, nb;
22 
23 int main() {
24     while(~scanf("%d%d", &na, &nb)) {
25         scanf("%d%d", &k, &m);
26         for(int i = 1; i <= na; i++) {
27             scanf("%d", &a[i]);
28         }
29         for(int i = 1; i <= nb; i++) {
30             scanf("%d", &b[i]);
31         }
32         if(a[k] < b[nb-m+1]) {
33             printf("YES
");
34         }
35         else {
36             printf("NO
");
37         }
38     }
39 }   
原文地址:https://www.cnblogs.com/kirai/p/4751825.html