单项选择题
A.i=k/n, j=k%m B.i=k/m, j=k%m C.i=k/n, j=k%n D.i=k/m, j=k%n
A.4 B.5 C.6 D.7
A.rear-length B.(rear-length+m) mod m C.(1+rear+m-length) mod m D.m-length