# RareSkills Authors - Converting Algebraic Circuits to R1CS (Highlights) ![rw-book-cover|256](https://static.wixstatic.com/media/935a00_4ac9f25e74a346af909f37a9bd6b6dcf~mv2.png/v1/fill/w_1000,h_192,al_c,q_85,usm_0.66_1.00_0.01/935a00_4ac9f25e74a346af909f37a9bd6b6dcf~mv2.png) ## Highlights - By convention, the first element is always 1 to make some calculations easier, which we will demonstrate later. ([View Highlight](https://read.readwise.io/read/01hs8n08316vwjv8rpk5z4hecg)) ^694480496 #favorite - rank one constraint systems require exactly one multiplication per constraint ([View Highlight](https://read.readwise.io/read/01hs8m6qkm0eksmmhnja32mw7z)) ^694478296 - Specifically, A, B, and C are matrices with the same number of columns as the witness, and each column represents the same variable the index is using. ([View Highlight](https://read.readwise.io/read/01hs8mjvwwd4dty1886d18j6e7)) ^694479113 - The number of rows will correspond to the number of constraints in the circuit. ([View Highlight](https://read.readwise.io/read/01hs8mjm33hrk4merb6pcv9vcs)) ^694479108 - Multiplication is element-wise, not matrix multiplication. ([View Highlight](https://read.readwise.io/read/01hs8mnfsxzq6d5tsqn41a72d2)) ^694479278