A. George and Accommodation
time limit per test1 second
memory limit per test256 megabytes
inputstandard input
outputstandard output
George has recently entered the BSUCP (Berland State University for Cool Programmers). George has a friend Alex who has also entered the university. Now they are moving into a dormitory.

George and Alex want to live in the same room. The dormitory has n rooms in total. At the moment the i-th room has pi people living in it and the room can accommodate qi people in total (pi ≤ qi). Your task is to count how many rooms has free place for both George and Alex.

Input
The first line contains a single integer n (1 ≤ n ≤ 100) — the number of rooms.

The i-th of the next n lines contains two integers pi and qi (0 ≤ pi ≤ qi ≤ 100) — the number of people who already live in the i-th room and the room’s capacity.

Output
Print a single integer — the number of rooms where George and Alex can move in.

Examples
input
3
1 1
2 2
3 3
output
0
input
3
1 10
0 10
10 10
output
问题链接：
http://codeforces.com/problemset/problem/467/A

问题简述：
george和alex要住进去宿舍，看看已有的房间和是否能容纳两个人进去，并统计这样的房间的个数。

问题分析：
创建动态数组来存储房间数。

贴上代码↓↓↓

#include <iostream>
using namespace std;
void cal(int*&a, int*&b, int n);
int main()
{
	int n,*a,*b,  i,  k=0;
	cin >> n;
	if (n >= 1 && n <= 100)
	{
		
		cal(a, b, n);
		for (i = 0; i < n; i++)
		{

			cin >> a[i];
			cin >> b[i];
			if (b[i] - 2 >= a[i])
				k++;
		}
		
		
			
			cout << k;
		
		delete[]a;
		delete[]b;
		a = b = NULL;
	}

}
void cal(int*&a, int*&b, int n)
{
	a = new int[n];
	b = new int[n];
}