Couldn't read shader file on Sierra

I just trying the same code as shader example 01 and got the following errors.

[ error ] ofShader: setupShaderFromFile(): couldn't load GL_VERTEX_SHADER shader  from "shadersGL3/shader.vert"
[ error ] ofShader: setupShaderFromFile(): couldn't load GL_FRAGMENT_SHADER shader  from "shadersGL3/shader.frag"
[ error ] ofShader: bindDefaults(): trying to link GLSL program, but no shaders created yet
[ error ] ofShader: linkProgram(): trying to link GLSL program, but no shaders created yet

Does anyone know how I can fix this problem.

OS macOS Sierra version 10.12.5
Xcode 8.3

Thanks!

Solved: The problem was my file structure.