Language: C++

import java.io.*;

class Main {
	public static void main(String args[]) {
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
			String s[], t;
			int i, j, ans, l, m;
			boolean flag = false;
			while((t = reader.readLine()) != null) {
				s = t.split(" ");
				i = s[0].length()-1 >= s[1].length()-1 ? s[0].length()-1 : s[1].length()-1;
				j = s[0].length()-1 <= s[1].length()-1 ? s[0].length()-1 : s[1].length()-1;
				l = s[0].length()-1 >= s[1].length()-1 ? 0 : 1;
				int a[][] = {new int[i+1], new int[j+1]};
				for(int k = 0;k < i+1;k++) {
					a[0][k] = s[l].charAt(k)-'0';
				}
				int f = Math.abs(l-1);
				for(int k = 0;k < j+1;k++) {
					a[1][k] = s[f].charAt(k)-'0';
				}
				while(i>=0) {
					if(j >= 0)
						m = a[1][j];
					else
						m = 0;
					a[0][i] = a[0][i] + m;
					if(a[0][i]>9) {
						if(i>0) {
							a[0][i] %= 10; 
							a[0][i-1]++;
						}
						else if(i==0){
							flag = true;
							break;
						}
					}
					i--;
					j--;
				}
				ans = flag ? a[0].length+1 : a[0].length;
				System.out.println(ans);
				flag = false;
			}
		}
		catch(IOException e) {
			System.out.println(e);
		}
	}
}

Compiler output:
a.cc:1:1: error: 'import' does not name a type
    1 | import java.io.*;
      | ^~~~~~
a.cc:1:1: note: C++20 'import' only available with '-fmodules-ts'
a.cc:4:15: error: expected ':' before 'static'
    4 |         public static void main(String args[]) {
      |               ^~~~~~~
      |               :
a.cc:4:33: error: 'String' has not been declared
    4 |         public static void main(String args[]) {
      |                                 ^~~~~~
a.cc:51:2: error: expected ';' after class definition
   51 | }
      |  ^
      |  ;
a.cc: In static member function 'static void Main::main(int*)':
a.cc:6:25: error: 'BufferedReader' was not declared in this scope
    6 |                         BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
      |                         ^~~~~~~~~~~~~~
a.cc:7:25: error: 'String' was not declared in this scope
    7 |                         String s[], t;
      |                         ^~~~~~
a.cc:9:25: error: 'boolean' was not declared in this scope; did you mean 'bool'?
    9 |                         boolean flag = false;
      |                         ^~~~~~~
      |                         bool
a.cc:10:32: error: 't' was not declared in this scope
   10 |                         while((t = reader.readLine()) != null) {
      |                                ^
a.cc:10:36: error: 'reader' was not declared in this scope
   10 |                         while((t = reader.readLine()) != null) {
      |                                    ^~~~~~
a.cc:10:58: error: 'null' was not declared in this scope
   10 |                         while((t = reader.readLine()) != null) {
      |                                                          ^~~~
a.cc:11:33: error: 's' was not declared in this scope
   11 |                                 s = t.split(" ");
      |                                 ^
a.cc:15:37: error: declaration of 'a' as multidimensional array must have bounds for all dimensions except the first
   15 |                                 int a[][] = {new int[i+1], new int[j+1]};
      |                                     ^
a.cc:17:41: error: 'a' was not declared in this scope
   17 |                                         a[0][k] = s[l].charAt(k)-'0';
      |                                         ^
a.cc:19:41: error: 'Math' was not declared in this scope
   19 |                                 int f = Math.abs(l-1);
      |                                         ^~~~
a.cc:21:41: error: 'a' was not declared in this scope
   21 |                                         a[1][k] = s[f].charAt(k)-'0';
      |                                         ^
a.cc:25:53: error: 'a' was not declared in this scope
   25 |                                                 m = a[1][j];
      |                                                     ^
a.cc:28:41: error: 'a' was not declared in this scope
   28 |                                         a[0][i] = a[0][i] + m;
      |                                         ^
a.cc:35:57: error: 'flag' was not declared in this scope
   35 |                                                         flag = true;
      |                                                         ^~~~
a.cc:42:39: error: 'flag' was not declared in this scope
   42 |                                 ans = flag ? a[0].length+1 : a[0].length;
      |                                       ^~~~
a.cc:42:46: error: 'a' was not declared in this scope
   42 |                                 ans = flag ? a[0].length+1 : a[0].length;
      |                                              ^
a.cc:43:33: error: 'System' was not declared in this scope
   43 |                                 System.out.println(ans);
      |                                 ^~~~~~
a.cc:47:23: error: 'IOException' does not name a type
   47 |                 catch(IOException e) {
      |                       ^~~~~~~~~~~
a.cc:48:25: error: 'System' was not declared in this scope
   48 |                         System.out.println(e);
      |                         ^~~~~~
a.cc:48:44: error: 'e' was not declared in this scope
   48 |                         System.out.println(e);
      |                                            ^