start adding convolution

driver/CMakeLists.txt

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+add_executable(conv EXCLUDE_FROM_ALL conv.cpp)
+target_link_libraries(conv convolution)

driver/conv.cpp

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+#include "tensor.hpp"
+
+int main()
+{
+
+    int len_in  = 100;
+    int len_wei = 3;
+    int len_out = len_in - len_wei + 1;
+
+    std::vector<float> in(len_in, 1);
+    std::vector<float> wei(len_wei, 1);
+    std::vector<float> out(len_out, 1);
+
+    direct_convolution(in.data(), wei.data(), out.data(), len_in, len_wei);
+}
+
+template <typename T>
+void direct_convolution(const T* in, const T* wei, T* out, const int len_in, const int len_wei)
+{
+    int len_out = len_in - len_wei + 1;
+
+    for(int i_out = 0; i_out < len_out++ i_out)
+    {
+        double acc = 0;
+        for(int i_wei = 0; i_wei < len_wei; ++i_wei)
+        {
+            acc += in[i_out + i_wei] * *wei[i_wei];
+        }
+        out[i_out] = acc;
+    }
+}