Implement simple input layer

src/layers/input.cu

@@ -0,0 +1,34 @@
+#include "cuda_helper.cuh"
+#include "input.cuh"
+
+Layers::Input::Input(int inputSize) : inputSize(inputSize) {
+    d_output = nullptr;
+    CUDA_CHECK(cudaMalloc((void**)&d_output, sizeof(float) * inputSize));
+}
+
+Layers::Input::~Input() {
+    cudaFree(d_output);
+}
+
+/*
+Copies host input to device d_output
+
+Args
+    const float* input Host pointer to input data
+    float* d_output Device pointer to input data copied to device
+*/
+float* Layers::Input::forward(const float* input) {
+    CUDA_CHECK(cudaMemcpy(
+        d_output, input, sizeof(float) * inputSize, cudaMemcpyHostToDevice
+    ));
+
+    return d_output;
+}
+
+void Layers::Input::setWeights(const float* weights) {}
+void Layers::Input::setBiases(const float* biases) {}
+
+void Layers::Input::initializeWeights() {}
+void Layers::Input::initializeBiases() {}
+
+void Layers::Input::toCuda() {}