Codeforces Round #335 (Div. 2) C.Sorting Railway Cars

C. Sorting Railway Cars

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

An infinitely long railway has a train consisting of n cars, numbered from1 to n (the numbers of all the cars are distinct) and positioned in arbitrary order. David Blaine wants to sort the railway cars in the order of increasing numbers. In one move he can make one of the cars disappear from its place and teleport it either to the beginning of the train, or to the end of the train, at his desire. What is the minimum number of actions David Blaine needs to perform in order to sort the train?

Input

The first line of the input contains integer n (1 ≤ n ≤ 100 000) — the number of cars in the train.

The second line contains n integers p_i (1 ≤ p_i ≤ n,p_i ≠ p_j ifi ≠ j) — the sequence of the numbers of the cars in the train.

Output

Print a single integer — the minimum number of actions needed to sort the railway cars.

Sample test(s)

Input

54 1 2 5 3

Output

2

Input

44 1 3 2

Output

2

Note

In the first sample you need first to teleport the 4-th car, and then the5-th car to the end of the train.

题意：给出n个数（1~n）,每次可以将任意一个数放到头部或末尾，求最少变化次数使得数列最后从小到大排列。

思路：细心一看是求最长的等差数列（公差为1）的长度s，结果便是n-s;

#include <stdio.h>#define MAX 100005int a[MAX],c[MAX];int main(){    int i,n, max = 0;    scanf("%d",&n);    {        for(i=0;i<n;i++){            scanf("%d",&a[i]);            c[a[i]] = c[a[i]-1] + 1;            if(c[a[i]] > max) max = c[a[i]];        }        printf("%d\n",n - max);    }}