diff --git a/src/c/rockPaperScissors.c b/src/c/rockPaperScissors.c
index 4f482e4..a8477e6 100644
--- a/src/c/rockPaperScissors.c
+++ b/src/c/rockPaperScissors.c
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
 
 #include "rockPaperScissors.h"
 
@@ -41,3 +42,10 @@ int wasGameWon(roundsToWin, playerWins, computerWins){
     return winner;
 }
 
+bool validatePlayerInput(int playerInput){
+    bool inputValid;
+    if (playerInput == ROCK || PAPER || SCISSORS){
+        inputValid = true;
+    }
+    return inputValid;
+}
\ No newline at end of file
diff --git a/src/c/rockPaperScissors.h b/src/c/rockPaperScissors.h
index e3eb73f..d6df3ec 100644
--- a/src/c/rockPaperScissors.h
+++ b/src/c/rockPaperScissors.h
@@ -1,6 +1,8 @@
 #ifndef ROCKPAPERSCISSORS_H
 #define ROCKPAPERSCISSORS_H
 
+#include <stdbool.h>
+
 enum inputOptions{
     ROCK,
     PAPER,
@@ -22,6 +24,7 @@ enum gameWinner{
 
 int findWinner(int inputPlayer, int inputComputer);
 int getComputerInput();
-int wasGameWon(roundsToWin, playerWins, computerWins);
+int wasGameWon(int roundsToWin, int playerWins, int computerWins);
+bool validatePlayerInput(int playerInput);
 
 #endif
\ No newline at end of file
diff --git a/test/c/test_rockPaperScissors.c b/test/c/test_rockPaperScissors.c
index 49a6b99..69d6761 100644
--- a/test/c/test_rockPaperScissors.c
+++ b/test/c/test_rockPaperScissors.c
@@ -182,11 +182,25 @@ void test_rockPaperScissors_gameWasNotWon(void)
     TEST_ASSERT_EQUAL_INT(NOTWONYET, result);
 }
 
+void test_rockPaperScissors_validPlayerInput(void)
+{
+    /* arrange */
+    //Hier die Werte eingeben
+    bool result;
+    int playerInput = 1;
+
+    /* act */
+    //Die Funktion wird ausgeführt
+    result = validatePlayerInput(playerInput);
+
+    /* assert */
+    //Vergleichen
+    TEST_ASSERT_EQUAL_INT(true, result);
+}
+
 #endif // TEST
 
 /*Testcases:
-rockPaperScissors_playerGetsBestOutOf3
-rockPaperScissors_computerGetsBestOutOf3
 rockPaperScissors_outputResult
 rockPaperScissors_invalidInput
 */
\ No newline at end of file