Detection of pattern in a list

[Josesec]

From the list below I would like to detect the elements of the list (5 elements in the list below) that have a string ending by "0002". The problem is in the detection of the "end" of each string because some elements of the list have more than one string.

$1
[1] 1000262

$554
[1] 554000002 554000017 554000022 554000087 554000170 554000229 554000381 554000515
[9] 554000595 554000635 554000680

$653
[1] 653000002 653000033 653000126 653000400 653000712

$654
[1] 654000579

$655
[1] 655000620

[technocrat]

@Josesec

[1] 554000002 554000017 554000022 554000087 554000170 554000229 554000381 554000515

Is this a single string?

"554000002 554000017 554000022 554000087 554000170 554000229 554000381 554000515"

See the FAQ: How to do a minimal reproducible example reprex for beginners for a way to eliminate ambiguities such as this.

[FJCC]

I'm really not sure what your criterion is for the search. This gets the answer of 5 that you mentioned.

TheList <- list(`1` = 1000262,
                `554` = c(554000002, 554000017, 554000022, 554000087, 
                          554000170, 554000229, 554000381, 554000515,
                          554000595, 554000635, 554000680),
                `653` = c(653000002, 653000033, 653000126, 653000400, 653000712),
                `654` = c(654000579),
                `655` = c(655000620))
TheList
#> $`1`
#> [1] 1000262
#> 
#> $`554`
#>  [1] 554000002 554000017 554000022 554000087 554000170 554000229 554000381
#>  [8] 554000515 554000595 554000635 554000680
#> 
#> $`653`
#> [1] 653000002 653000033 653000126 653000400 653000712
#> 
#> $`654`
#> [1] 654000579
#> 
#> $`655`
#> [1] 655000620
Counts <- sapply(TheList, function(x) sum(grepl("0002",x)))
Counts
#>   1 554 653 654 655 
#>   1   3   1   0   0
sum(Counts)
#> [1] 5

^{Created on 2022-12-31 with reprex v2.0.2}

[Josesec]

Thank you for your answer. For me this is an element of the list with 8 different strings.

[Josesec]

Thank you for your answer. This is not exactly what I am looking for. I am looking for this answer:

[1] FALSE TRUE TRUE FALSE FALSE

For example: for the first element of the list there is no string ending by "0002". In the second element of the list the first string ( 5540000002) is ending by "0002".

[FJCC]

TheList <- list(`1` = 1000262,
                 `554` = c(554000002, 554000017, 554000022, 554000087, 
                           554000170, 554000229, 554000381, 554000515,
                           554000595, 554000635, 554000680),
                 `653` = c(653000002, 653000033, 653000126, 653000400, 
                           653000712),
                 `654` = c(654000579),
                 `655` = c(655000620))
sapply(TheList, function(x) any(grepl("0002$",x)))
    1   554   653   654   655 
FALSE  TRUE  TRUE FALSE FALSE