Language: C++

//import java.io.File;
import java.util.Scanner;

class Main{
	static int[] arr;
	public static void main(String[] args) {
try{
		//Scanner scan = new Scanner(new File("in.txt"));
		Scanner scan = new Scanner(System.in);


		int input1 = scan.nextInt();
		arr = new int[input1];
		for(int i = 0; i < input1; i++) {
			arr[i] = scan.nextInt();
		}

		System.out.println(getCarpet(0,input1-1,1)+1);
		

}catch(Exception e) {
	e.printStackTrace();
}
	}

	//start,end,height
	static int getCarpet(int _s, int _e, int _h) {
//System.out.println(_s+","+_e+","+_h);
		int sum = 0;
		boolean flag = true;

		for(int i = _h; flag; i++) {
			int start = -1;
			boolean dummyFlag = true;
			boolean dummyFlag2 = true;
			for(int j = _s; j <= _e; j++) {
				if(arr[j]-i > 0) {
					dummyFlag = false;
					if(start == -1) {
						start = j;
					}
				}else {
					dummyFlag2 = false;
					if(start != -1) {
						sum += getCarpet(start,j-1,i+1)+1;
						flag = false;
						start = -1;
					}
				}
			}
			if(start != -1 && !dummyFlag2) {
				sum += getCarpet(start,_e,i+1)+1;
				break;
			}
			//if(flag && start == -1) break;
			if(dummyFlag) break;
		}

		return sum;
	}
}

Compiler output:
a.cc:2:1: error: 'import' does not name a type
    2 | import java.util.Scanner;
      | ^~~~~~
a.cc:2:1: note: C++20 'import' only available with '-fmodules-ts'
a.cc:5:19: error: expected unqualified-id before '[' token
    5 |         static int[] arr;
      |                   ^
a.cc:6:15: error: expected ':' before 'static'
    6 |         public static void main(String[] args) {
      |               ^~~~~~~
      |               :
a.cc:6:33: error: 'String' has not been declared
    6 |         public static void main(String[] args) {
      |                                 ^~~~~~
a.cc:6:42: error: expected ',' or '...' before 'args'
    6 |         public static void main(String[] args) {
      |                                          ^~~~
a.cc:61:2: error: expected ';' after class definition
   61 | }
      |  ^
      |  ;
a.cc: In static member function 'static void Main::main(int*)':
a.cc:9:17: error: 'Scanner' was not declared in this scope
    9 |                 Scanner scan = new Scanner(System.in);
      |                 ^~~~~~~
a.cc:12:30: error: 'scan' was not declared in this scope
   12 |                 int input1 = scan.nextInt();
      |                              ^~~~
a.cc:13:17: error: 'arr' was not declared in this scope
   13 |                 arr = new int[input1];
      |                 ^~~
a.cc:18:17: error: 'System' was not declared in this scope
   18 |                 System.out.println(getCarpet(0,input1-1,1)+1);
      |                 ^~~~~~
a.cc:21:8: error: 'Exception' does not name a type
   21 | }catch(Exception e) {
      |        ^~~~~~~~~
a.cc:22:9: error: 'e' was not declared in this scope
   22 |         e.printStackTrace();
      |         ^
a.cc: In static member function 'static int Main::getCarpet(int, int, int)':
a.cc:30:17: error: 'boolean' was not declared in this scope; did you mean 'bool'?
   30 |                 boolean flag = true;
      |                 ^~~~~~~
      |                 bool
a.cc:32:33: error: 'flag' was not declared in this scope
   32 |                 for(int i = _h; flag; i++) {
      |                                 ^~~~
a.cc:34:33: error: expected ';' before 'dummyFlag'
   34 |                         boolean dummyFlag = true;
      |                                 ^~~~~~~~~
a.cc:35:33: error: expected ';' before 'dummyFlag2'
   35 |                         boolean dummyFlag2 = true;
      |                                 ^~~~~~~~~~
a.cc:37:36: error: 'arr' was not declared in this scope
   37 |                                 if(arr[j]-i > 0) {
      |                                    ^~~
a.cc:38:41: error: 'dummyFlag' was not declared in this scope
   38 |                                         dummyFlag = false;
      |                                         ^~~~~~~~~
a.cc:43:41: error: 'dummyFlag2' was not declared in this scope
   43 |                                         dummyFlag2 = false;
      |                                         ^~~~~~~~~~
a.cc:51:44: error: 'dummyFlag2' was not declared in this scope
   51 |                         if(start != -1 && !dummyFlag2) {
      |                                            ^~~~~~~~~~
a.cc:56:28: error: 'dummyFlag' was not declared in this scope
   56 |                         if(dummyFlag) break;
      |                            ^~~~~~~~~