Problem:
Score : 300 points

Problem Statement

Given is a permutation P_1, \ldots, P_N of 1, \ldots, N.
Find the number of integers i (1 \leq i \leq N) that satisfy the following condition:

For any integer j (1 \leq j \leq i), P_i \leq P_j.

Constraints

1 \leq N \leq 2 \times 10^5

P_1, \ldots, P_N is a permutation of 1, \ldots, N.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
P_1 ... P_N

Output

Print the number of integers i that satisfy the condition.

Sample Input 1

5
4 2 5 1 3

Sample Output 1

3

i=1, 2, and 4 satisfy the condition, but i=3 does not - for example, P_i > P_j holds for j = 1.

Similarly, i=5 does not satisfy the condition, either. Thus, there are three integers that satisfy the condition.

Sample Input 2

4
4 3 2 1

Sample Output 2

4

All integers i (1 \leq i \leq N) satisfy the condition.

Sample Input 3

6
1 2 3 4 5 6

Sample Output 3

1

Only i=1 satisfies the condition.

Sample Input 4

8
5 7 4 2 6 8 1 3

Sample Output 4

4

Sample Input 5

1
1

Sample Output 5

1

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

import sys, math
from itertools import permutations, combinations
from collections import defaultdict, Counter
from math import factorial
from bisect import bisect_right

sys.setrecursionlimit(10**7)
N = int(input())
P = list(map(int, input().split()))

rP = list(reversed(P))
seq = rP.copy()

LIS = [seq[0]]
for i in range(1, N):
    if seq[i] >= LIS[-1]:
        LIS.append(seq[i])
    else:
        LIS[bisect_right(LIS, seq[i])] = seq[i]

print(len(LIS))