#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>

#define _CRT_SECURE_NO_WARNINGS
#define TLong long long

// qsort(array, size, sizeof(int),comp);
int comp(const int *a,const int *b){
	return (*a - *b);
}

int main(int argc, char const *argv[])
{
	int N,H;
	int *a,*b,throw = 0;
	scanf("%d%d",&N,&H);
	a = (int *)malloc(sizeof(int) * N);
	b = (int *)malloc(sizeof(int) * N);
	for (int i = 0; i < N; ++i)	scanf(" %d%d",&a[i],&b[i]);
	qsort(a,N,sizeof(int),comp);
	for (int i = 0; i < N; ++i)
	{
		if(a[N - 1] <= b[i]){
			H -= b[i];
			++throw;
		}
	}
	printf("%d\n", throw + H / a[N - 1]);
	return 0;
}