#5142. [Usaco2017 Dec]Haybale Feast

内存限制:128 MiB 时间限制:10 Sec


Farmer John is preparing a delicious meal for his cows! In his barn, he has NN haybales (1≤N≤100,0
00). The iith haybale has a certain flavor Fi (1≤Fi≤10^9) and a certain spiciness Si(1≤Si≤10^9).
The meal will consist of a single course, being a contiguous interval containing one or more consecu
tive haybales (Farmer John cannot change the order of the haybales). The total flavor of the meal is
 the sum of the flavors in the interval. The spiciness of the meal is the maximum spiciness of all h
aybales in the interval.Farmer John would like to determine the minimum spiciness his single-course 
meal could achieve, given that it must have a total flavor of at least MM (1≤M≤10^18).
给长度为n<=1e5的两个序列f[], s[] <= 1e9和一个long long M。
如果[1, n] 的一个子区间[a, b]满足 f[a]+f[a+1]+..+f[b] >= M, 我们就称[a, b]合法
,一个合法区间[a, b]的值为max(s[a], s[a+1], ..., s[b])。


The first line contains the integers N and M, 
the number of haybales and the minimum total flavor the meal must have, respectively. 
The next N lines describe the N haybales with two integers per line, 
first the flavor F and then the spiciness S.


Please output the minimum spiciness in a single course meal that satisfies the minimum flavor requirement. 
There will always be at least one single-course meal that satisfies the flavor requirement.



5 10
4 10
6 15
3 5
4 9
3 6