In Ma$$nActivty$.$java add this code

findViewByld$($R$.$id$.$Subtract$).$setOnClickListener$($new android.view.View.OnClickListener$()\{$

@ Override public void onClick$($android$.$view.View view$)\{$ android. widget.EditText InputWidget $=$ findViewByld$($

R$.$id$.$ NumberO$1$ number$01=$ Integer.parselnt$($InputWidget$.$getText$().$toString$())$;

InputWidget $=$ findViewByld$($R$.$id$.$NumberO$2).$

number$02=$ Integer.parselnt InputWidget.getText$().$toString$())$;

result $=$ number$01-$number$0$:

android. widget.EditText OutputWidget $=$ findViewByld$($

R$.$id$.$ Result$)$;

OutputWidget.setText$($Integer$.$toString$($result$))$;

$\}\})$;

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