The efficiency of gene expression programming (GEP) is low in processing complex gene with large length. In order to solve the problem, a novel algorithm with linear complexity was proposed. The main contributions include: 1) Analyzing the limit in conventional gene expression programming, 2) Proposing a novel LDecode algorithm to evaluate the fitness of chromosome speedy.The extensive experiments demonstrated that this algorithm is faster than traditional one by 4.5~5.1 times on different parameters, and the time complexity and space complexity are linear.
