diff --git a/src/main/c/VierGewinnt.c b/src/main/c/VierGewinnt.c
new file mode 100644
index 0000000..c4d1419
--- /dev/null
+++ b/src/main/c/VierGewinnt.c
@@ -0,0 +1,256 @@
+//Importiere wichtige Bibliotheken
+#include <stdio.h>
+#include <stdlib.h>
+
+//Definiere Feldgröße
+#define ROWS 6
+#define COLS 7
+
+// Definiere Farben
+#define RESET_COLOR "\033[0m"
+#define BLACK "\033[0;30m"
+#define RED "\033[0;31m"
+#define GREEN "\033[0;32m"
+#define YELLOW "\033[0;33m"
+#define BLUE "\033[0;34m"
+#define MAGENTA "\033[0;35m"
+#define CYAN "\033[0;36m"
+#define WHITE "\033[0;37m"
+
+
+//Funktionsprototyp für initializeBoard
+void initializeBoard(char board[ROWS][COLS]);
+
+//Funktionsprototyp für printBoard
+void printBoard(char board[ROWS][COLS]);
+
+// Funktionsprototyp für clearScreen
+void clearScreen();
+
+//Funktionsprototyp für isColumnFull
+int isColumnFull(char board[ROWS][COLS], int col);
+
+//Funktionsprototyp für dropPiece
+int dropPiece(char board[ROWS][COLS], int col, char player);
+//Funktionsprototyp für checkWin
+int checkWin(char board[ROWS][COLS], char player);
+// Funktionsprototyp für checkHorizontal
+int checkHorizontal(char board[ROWS][COLS], char player);
+
+// Funktionsprototyp für checkVertical
+int checkVertical(char board[ROWS][COLS], char player);
+
+// Funktionsprototyp für checkDiagonalLR
+int checkDiagonalLR(char board[ROWS][COLS], char player);
+
+// Funktionsprototyp für checkDiagonalRL
+int checkDiagonalRL(char board[ROWS][COLS], char player);
+
+// Funktionsprototyp für showMessage
+void showMessage(const char* messageColor, const char* message);
+//Funktionsprototyp für showInvalidInputMessage 
+void showInvalidInputMessage();
+
+//Funktionsprototyp für showColumnFullMessage
+void showColumnFullMessage();
+
+//Funktionsprototyp für showWinMessage
+void showWinMessage(int player);
+
+
+//Write starter function
+int main_function() {
+    char board[ROWS][COLS];
+    int currentPlayer = 1; // Spieler 1 beginnt
+
+    initializeBoard(board);
+    printBoard(board);
+
+    int column;
+    while (1) {
+        printf(YELLOW"Spieler %d, wähle eine Spalte (1-7): "RESET_COLOR, currentPlayer);
+
+        scanf("%d", &column);
+        if (column < 1 || column > 7) {
+            showInvalidInputMessage();
+            continue;
+        }
+
+        column--;
+
+        if (isColumnFull(board, column)) {
+            showColumnFullMessage();
+            continue;
+        }
+
+        if (dropPiece(board, column, (currentPlayer == 1) ? 'X' : 'O')) {
+            printBoard(board);
+            if (checkWin(board, (currentPlayer == 1) ? 'X' : 'O')) {
+                showWinMessage(currentPlayer);
+                break;
+            }
+
+            currentPlayer = (currentPlayer == 1) ? 2 : 1;
+        }
+    }
+
+    return 0;
+}
+// Write initializeBoard function
+void initializeBoard(char board[ROWS][COLS]) {
+    for (int i = 0; i < ROWS; i++) {
+        for (int j = 0; j < COLS; j++) {
+            board[i][j] = ' ';
+        }
+    }
+}
+
+
+// Write printBoard function
+void printBoard(char board[ROWS][COLS]) {
+    clearScreen();
+    printf("\n");
+
+    for (int i = 0; i < ROWS; i++) {
+        for (int j = 0; j < COLS; j++) {
+            printf("| %c ", board[i][j]);
+        }
+        printf("|\n");
+
+        for (int j = 0; j < COLS; j++) {
+            printf("----");
+        }
+        printf("-\n");
+    }
+
+    printf("  1   2   3   4   5   6   7\n\n");
+}
+// Write clearScreen function
+void clearScreen() {
+#ifdef _WIN32
+    system("cls");
+#else
+    system("clear");
+#endif
+}
+
+// Write isColumnFull function
+int isColumnFull(char board[ROWS][COLS], int col) {
+    return (board[0][col] != ' ');
+}
+
+//Write dropPiece function
+int dropPiece(char board[ROWS][COLS], int col, char player) {
+    for (int i = ROWS - 1; i >= 0; i--) {
+        if (board[i][col] == ' ') {
+            board[i][col] = player;
+            return 1;
+        }
+    }
+
+    return 0; // Column is full
+}
+
+
+// Write checkHorizontal function
+int checkHorizontal(char board[ROWS][COLS], char player) {
+    for (int row = 0; row < ROWS; row++) {
+        for (int col = 0; col <= COLS - 4; col++) {
+            if (board[row][col] == player &&
+                board[row][col + 1] == player &&
+                board[row][col + 2] == player &&
+                board[row][col + 3] == player) {
+                return 1;  // Gewonnen
+            }
+        }
+    }
+    return 0;
+}
+
+//Write checkVertical function
+int checkVertical(char board[ROWS][COLS], char player) {
+    for (int col = 0; col < COLS; col++) {
+        for (int row = 0; row <= ROWS - 4; row++) {
+            if (board[row][col] == player &&
+                board[row + 1][col] == player &&
+                board[row + 2][col] == player &&
+                board[row + 3][col] == player) {
+                return 1;  // Gewonnen
+            }
+        }
+    }
+    return 0;
+}
+
+
+
+// Write checkDiagonalLR function
+int checkDiagonalLR(char board[ROWS][COLS], char player) {
+    for (int row = 0; row <= ROWS - 4; row++) {
+        for (int col = 0; col <= COLS - 4; col++) {
+            if (board[row][col] == player &&
+                board[row + 1][col + 1] == player &&
+                board[row + 2][col + 2] == player &&
+                board[row + 3][col + 3] == player) {
+                return 1;  // Gewonnen
+            }
+        }
+    }
+    return 0;
+}
+
+
+
+
+// Write checkDiagonalRL function
+int checkDiagonalRL(char board[ROWS][COLS], char player) {
+    for (int row = 0; row <= ROWS - 4; row++) {
+        for (int col = 3; col < COLS; col++) {
+            if (board[row][col] == player &&
+                board[row + 1][col - 1] == player &&
+                board[row + 2][col - 2] == player &&
+                board[row + 3][col - 3] == player) {
+                return 1;  // Gewonnen
+            }
+        }
+    }
+    return 0;
+
+}
+
+// Write checkWin function
+int checkWin(char board[ROWS][COLS], char player) {
+    return checkHorizontal(board, player) ||
+           checkVertical(board, player) ||
+           checkDiagonalLR(board, player) ||
+           checkDiagonalRL(board, player);
+}
+
+
+// Write showMessage function
+void showMessage(const char* messageColor, const char* message) {
+    printf("%s%s"RESET_COLOR, messageColor, message);
+}
+
+// Write showInvalidInputMessage function
+void showInvalidInputMessage() {
+    showMessage(RED, "Ungültige Eingabe. Bitte wähle eine Spalte zwischen 1 und 7.\n");
+}
+
+
+
+
+// Write showColumnFullMessage function
+void showColumnFullMessage() {
+    showMessage(RED, "Die Spalte ist voll. Bitte wähle eine andere.\n");
+}
+
+
+
+// Write showWinMessage function
+void showWinMessage(int player) {
+    printf("Spieler %d hat gewonnen!\n", player);
+}
+
+
+
diff --git a/src/main/c/VierGewinnt.h b/src/main/c/VierGewinnt.h
new file mode 100644
index 0000000..689034c
--- /dev/null
+++ b/src/main/c/VierGewinnt.h
@@ -0,0 +1,20 @@
+#ifndef VIERGEWINNT_H
+#define VIERGEWINNT_H
+
+#define ROWS 6
+#define COLS 7
+
+void initializeBoard(char board[ROWS][COLS]);
+void printBoard(char board[ROWS][COLS]);
+int isColumnFull(char board[ROWS][COLS], int col);
+int dropPiece(char board[ROWS][COLS], int col, char player);
+int checkWin(char board[ROWS][COLS], char player);
+int checkHorizontal(char board[ROWS][COLS], char player);
+int checkVertical(char board[ROWS][COLS], char player);
+int checkDiagonalLR(char board[ROWS][COLS], char player);
+int checkDiagonalRL(char board[ROWS][COLS], char player);
+void showMessage(const char* messageColor, const char* message);
+void showInvalidInputMessage();
+void showColumnFullMessage();
+void showWinMessage(int player);
+#endif
diff --git a/src/test/c/test_VierGewinnt.c b/src/test/c/test_VierGewinnt.c
new file mode 100644
index 0000000..1f14b9f
--- /dev/null
+++ b/src/test/c/test_VierGewinnt.c
@@ -0,0 +1,151 @@
+#include "unity.h"
+#include "VierGewinnt.h"  
+
+void setUp(void) {
+}
+
+void tearDown(void) {
+}
+
+
+void test_dropPiece_ValidMove(void) {
+    char board[6][7];
+    initializeBoard(board);
+
+    TEST_ASSERT_EQUAL_INT(1, dropPiece(board, 3, 'X')); 
+}
+
+
+void test_dropPiece_FullColumn(void) {
+    char board[6][7] = {
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'}
+    };
+
+    TEST_ASSERT_EQUAL_INT(0, dropPiece(board, 3, 'X'));  // Spalte ist voll, sollte 0 zurückgeben
+}
+
+
+void test_checkWin_Horizontal_X(void) {
+    char board[6][7] = {
+        {'X', 'X', ' ', ' ', ' ', ' ', ' '},
+        {'O', 'O', 'O', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'X', 'X', 'X', 'X', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'X'));  // Horizontale Gewinnsituation für 'X'
+}
+
+void test_checkWin_Horizontal_O(void) {
+    char board[6][7] = {
+        {'X', 'X', ' ', ' ', ' ', ' ', ' '},
+        {'O', 'O', 'O', 'O', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'X', 'X', ' ', 'X', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'O'));  // Horizontale Gewinnsituation für 'X'
+}
+
+void test_checkWin_Diagonal_X(void) {
+    char board[6][7] = {
+        {'X', 'X', ' ', ' ', ' ', ' ', ' '},
+        {'O', 'O', 'O', 'X', ' ', ' ', ' '},
+        {' ', 'X', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'X', 'X', 'X', 'X', ' ', ' '},
+        {' ', ' ', ' ','X', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', 'X', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'X'));  // Horizontale Gewinnsituation für 'X'
+}
+
+
+
+
+
+void test_checkWin_Diagonal_O(void) {
+    char board[6][7] = {
+        {'X', 'X', ' ', ' ', ' ', ' ', ' '},
+        {'O', 'O', 'O', 'X', ' ', ' ', ' '},
+        {' ', 'O', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'X', 'O', 'X', 'X', ' ', ' '},
+        {' ', ' ', ' ','O', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', 'X', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'O'));  // Horizontale Gewinnsituation für 'X'
+}
+
+
+
+
+
+
+
+void test_checkWin_Vertical_X(void) {
+    char board[6][7] = {
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'X'));  // Vertikale Gewinnsituation für 'X'
+}
+
+
+
+void test_checkWin_Vertical_O(void) {
+    char board[6][7] = {
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'O', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'O'));  // Vertikale Gewinnsituation für 'X'
+}
+void test_checkWin_NoWinner(void) {
+char board[6][7] = {
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'}
+    };
+
+
+
+
+    TEST_ASSERT_EQUAL_INT(0, checkWin(board, 'X'));  // Kein Gewinner, horizontale Reihe ist voll
+    TEST_ASSERT_EQUAL_INT(0, checkWin(board, 'O'));  // Kein Gewinner, horizontale Reihe ist voll
+}
+
+void test_isColumnFull(void) {
+    char board[6][7] = {
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'},
+        {'X', 'O', 'X', 'O', 'X', 'O', 'X'},
+        {'O', 'X', 'O', 'X', 'O', 'X', 'O'}
+    };
+
+    TEST_ASSERT_EQUAL_INT(1, isColumnFull(board, 3));  // Column 3 is full
+}
+
diff --git a/src/test/c/test_test.c b/src/test/c/test_test.c
deleted file mode 100644
index 4f61ea7..0000000
--- a/src/test/c/test_test.c
+++ /dev/null
@@ -1,28 +0,0 @@
-#ifdef TEST
-
-#include "unity.h"
-
-#include "test.h"
-
-void setUp(void)
-{
-}
-
-void tearDown(void)
-{
-}
-
-void test_test__return_5(void)
-{
-    /* arrange */
-	int expected = 5;
-	int actual;
-
-    /* act */
-	actual = return_5();
-
-    /* assert */
-	TEST_ASSERT_EQUAL_INT(expected, actual);
-}
-
-#endif // TEST