Zigzag

input/code.cpp: In function 'int main()':
input/code.cpp:23:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
input/code.cpp:26:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&inp[i]);
                            ^

#include <cstdio>
#include <queue>
#include <algorithm>
#include <vector>
#include <set>
#include <cstdlib>

#define all(x) (x).begin(),x.end()

#define pb push_back
#define mp make_pair
#define x1 first
#define x2 second.first
#define x3 second.second
#define trip(a,b,c) mp(a,mp(b,c))

using namespace std;
const int inf = 1000000007;

int main()
{
    int n;
    scanf("%d",&n);
    vector<int> inp(n);
    for(int i=0;i<n;i++)
        scanf("%d",&inp[i]);

    vector<int> iinp;
    for(int i=0;i<n;i++)
        if(i==0 || inp[i]!=inp[i-1])
            iinp.push_back(inp[i]);

    inp = iinp;

    n = inp.size();

    if(n==1)
    {
        puts("1");
        return 0; 
    }
    if(n==2)
    {
        puts("2");
        return 0;
    }

    bool inc = inp[1]>inp[0];

    int cnt = 0;

    for(int i=2;i<n;i++)
    {
        bool inc2 = (inp[i]>inp[i-1]);
        if(inc != inc2)
            cnt++;
        inc = inc2;
    }
    printf("%d\n",cnt+2);

}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED