diff --git a/units/on_screen_keyboard.cpp b/units/on_screen_keyboard.cpp
index 0a5dc15..c96bfdc 100644
--- a/units/on_screen_keyboard.cpp
+++ b/units/on_screen_keyboard.cpp
@@ -164,7 +164,7 @@ void OnScreenKeyboard::setLayout()
     allChars = use_char_symbol ? allChars + char_symbol : allChars;
 
     layout.clear();
-    for (int i = 0; i < allChars.length(); ++i)
+    for (int i = 0; i < (int)allChars.length(); ++i)
     {
         key_t key;
         key.col = index_col;
@@ -208,7 +208,7 @@ void OnScreenKeyboard::checkInput()
 // Disminuye en una columna la posición del cursor
 void OnScreenKeyboard::decCursorCol()
 {
-    cursor.col = cursor.col > 0 ? --cursor.col : columns - 1;
+    cursor.col = cursor.col > 0 ? cursor.col - 1 : columns - 1;
 }
 
 // Incrementa en una columna la posición del cursor
@@ -220,7 +220,7 @@ void OnScreenKeyboard::incCursorCol()
 // Disminuye en una fila la posición del cursor
 void OnScreenKeyboard::decCursorRow()
 {
-    cursor.row = cursor.row > 0 ? --cursor.row : rows - 1;
+    cursor.row = cursor.row > 0 ? cursor.row - 1 : rows - 1;
 }
 
 // Aumenta en una fila la posición del cursor
@@ -243,7 +243,7 @@ void OnScreenKeyboard::updateCursor()
 void OnScreenKeyboard::addChar()
 {
     const int pos = cursor.col + cursor.row * columns;
-    if (pos < layout.size())
+    if (pos < (int)layout.size())
         output = output + layout.at(pos).caption;
 }
 
@@ -271,7 +271,7 @@ void OnScreenKeyboard::render()
     SDL_RenderCopy(renderer, textureCursor, nullptr, &cursor.dest);
 
     const int pos = cursor.col + cursor.row * columns;
-    const string key = pos < layout.size() ? layout.at(pos).caption : "";
+    const string key = pos < (int)layout.size() ? layout.at(pos).caption : "";
     text->writeDX(TXT_CENTER | TXT_COLOR, cursor.dest.x + cursor.dest.w / 2, cursor.dest.y + cursor.dest.w / 4, key, 1, {0, 255, 0});
     text->write(dest.x + outputDest.x, dest.y + outputDest.y, output);
 }