Program baitap;
Uses crt;
Var A:array[1..200] of integer;
    i,n,max:integer;
Begin
Clrscr;
Write('Nhap do dai xau:'); Readln(n);
For i:=1 to n do
     Begin
     Write('Nhap phan tu thu ',i,':');
     Readln(A[i]);
     End;
Write('Day so vua nhap:');
For i:=1 to n do Write(A[i],' ');
Writeln(' ');
max:=A[1];
For i:=1 to n do If A[i]>max then max:=A[i];
Write('So lon nhat:',max);
Writeln(' ');
Write('Cac so am co trong day:');
For i:=1 to n do If A[i]<0 then Write(A[i],' ');
Writeln(' ');
Write('Cac so chan co trong day:');
For i:=1 to n do If A[i] mod 2=0 then write(A[i],' ');
Readln
End.

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Đã test code

#include<iostream>

using namespace std;

int main(){

int a[1000],n;

cin>>n;

for(int i=0;i<n;i++){cin>>a[i];}

for(int i=0;i<n;i++){cout<<a[i]<<" ";}

cout<<endl<<*max_element(a,a+n+1)<<endl;

for(int i=0;i<n;i++){

if(a[i]<0){cout<<a[i]<<" ";

}

cout<<endl;

for(int i=0;i<n;i++){

if(a[i]%2==0){cout<<a[i]<<" ";}

}

}

*Cái hàm *max_element() dùng để lấy phần tử lớn nhất trong mảng nhé