Problem:
Score : 200 points

Problem Statement

An X-layered kagami mochi (X ≥ 1) is a pile of X round mochi (rice cake) stacked vertically where each mochi (except the bottom one) has a smaller diameter than that of the mochi directly below it. For example, if you stack three mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, you have a 3-layered kagami mochi; if you put just one mochi, you have a 1-layered kagami mochi.

Lunlun the dachshund has N round mochi, and the diameter of the i-th mochi is d_i centimeters. When we make a kagami mochi using some or all of them, at most how many layers can our kagami mochi have?

Constraints

1 ≤ N ≤ 100

1 ≤ d_i ≤ 100

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
d_1
:
d_N

Output

Print the maximum number of layers in a kagami mochi that can be made.

Sample Input 1

4
10
8
8
6

Sample Output 1

3

If we stack the mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, we have a 3-layered kagami mochi, which is the maximum number of layers.

Sample Input 2

3
15
15
15

Sample Output 2

1

When all the mochi have the same diameter, we can only have a 1-layered kagami mochi.

Sample Input 3

7
50
30
50
100
50
80
30

Sample Output 3

4

Solution in C (GCC 5.4.1) (judge verdict: Accepted)

#include "stdio.h"

int N;

void sort(int A[]){
  for(int i; i < N; i++){
    int j = i;
    int tmp = 0;
    while(j >= 1 && A[j - 1] < A[j]){//逆
      tmp = A[j];
      A[j] = A[j - 1];
      A[j - 1] = tmp;
      j--;
    }
  }
}

void steps_mochi(int A[]){
  int mochi[N];
  int steps = 0;
  for(int i = 0; i < N; i++){
    mochi[i] = 0;
  }
  for(int j = 0; j < N; j++){
    if(A[j] >= A[j + 1]){
      mochi[j] = A[j];
    }
  }
  for(int k = 0; k < N; k++){
    if(mochi[k] != 0 && mochi[k] != mochi[k + 1]){
      steps++;
    }
  }
  printf("%d\n", steps);
}

int main(void){
  scanf("%d\n", &N);
  int A[N];

  for(int i = 0; i < N; i++){
    scanf("%d", &A[i]);
  }

  sort(A);

  A[N] = 0;

  steps_mochi(A);

  return 0;
}