I have a vector that should contain n sequences from 00 to 11 A = [00;01;02;03;04;05;06;07;08;09;10;11;00;01;02;03;04;05;06;07;08;09;10;11] and I would like to check that the sequence "00 - 11 " is always respected (no missing values). for example if A =[00;01;02; 04;05;06;07;08;09;10;11;00;01;02;03;04;05;06;07;08;09;10;11] (missing 03 in the 3rd position) For each missing value I would like to have back this information in another vector missing= [value_1,position_1; value_2, position_2; etc, etc] Can you help me?