Migrate input layer

include/layers/input.hpp

@@ -0,0 +1,66 @@
+#ifndef CUDANET_INPUT_LAYER_H
+#define CUDANET_INPUT_LAYER_H
+
+#include "layer.hpp"
+
+namespace CUDANet::Layers {
+
+/**
+ * @brief Input layer, just copies the input to the device
+ *
+ */
+class Input : public SequentialLayer {
+  public:
+    /**
+     * @brief Create a new Input layer
+     *
+     * @param inputSize Size of the input vector
+     */
+    explicit Input(int inputSize);
+
+    /**
+     * @brief Destroy the Input layer
+     *
+     */
+    ~Input();
+
+    /**
+     * @brief Forward pass of the input layer. Just copies the input to the
+     * device
+     *
+     * @param input Host pointer to the input vector
+     * @return Device pointer to the output vector
+     */
+    float* forward(const float* input);
+
+    /**
+     * @brief Get output size
+     *
+     * @return int output size
+     */
+    int getOutputSize();
+
+    /**
+     * @brief Get input size
+     *
+     * @return int input size
+     */
+    int getInputSize();
+
+  private:
+    int inputSize;
+
+    float* forwardCPU(const float* input);
+
+#ifdef USE_CUDA
+    float* d_output;
+
+    float* forwardCUDA(const float* input);
+    void   initCUDA();
+    void   delCUDA();
+#endif
+};
+
+}  // namespace CUDANet::Layers
+
+#endif  // CUDANET_INPUT_LAYER_H