摘要
The present issue of Science China Mathematics is devoted to the themes of Combinatorics, Coding theory and Cryptography （C3）.
The present issue of Science China Mathematics is devoted to the themes of Combinatorics,Codingtheory and Cryptography(C3).Combinatorics,coding theory and(modern)cryptography are relatively young as subjects of mathematics.These areas enjoyed tremendous growth in the second half of the twentieth century,and thetrend shows no signs of abating.Moreover,the first decade of the twenty-first century also witnessedintensified interactions between these subjects.This special issue showcases some aspects of C3andconnections among them.The purpose is two-fold.On the
