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>
void swap (int *x, int *y) {
  int temp;    // 値を一時保存する変数

  temp = *x;
  *x = *y;
  *y = temp;
}

/***
* pivotを決め、
* 全データをpivotを境目に振り分け、
* pivotの添え字を返す
***/
int partition (int array[], int left, int right) {
  int i, j, pivot;
  i = left;
  j = right+1;
  pivot = left;   // 先頭要素をpivotとする


  do {
    do { i++; } while (array[i] < array[pivot]);
    do { j--;  } while (array[pivot] < array[j]);
    // pivotより小さいものを左へ、大きいものを右へ
 //printf("   ");
    if (i < j) { swap(&array[i], &array[j]); }
  } while (i < j);


/*
while(i<j){
    while(array[i]<array[pivot]){i++;}
    while(array[j]>array[pivot]){j--;}
    if(i<j){swap(&array[i],&array[j]);}
}
*/
  swap(&array[pivot], &array[j]);   //pivotを更新

  return j;
}

/* クイックソート */
void quick_sort (int array[], int left, int right) {
  int pivot;

  if (left < right) {
      //printf("Q");
    pivot = partition(array, left, right);
    quick_sort(array, left, pivot-1);   // pivotを境に再帰的にクイックソート
    quick_sort(array, pivot+1, right);
  }
}
int main(void){
    int N,i,mochi[100];
    int total=1;
    scanf("%d",&N);
    for(i=0;i<N;i++)scanf("%d",&mochi[i]);
    
    quick_sort(mochi,0,N-1);
    
    for(i=1;i<N;i++){
        if(mochi[i]>mochi[i-1])total++;
    }
    printf("%d",total);
    
    return 0;
}