c# - Search max value and index inside Nested list -

i know can max value , index simple list in way

list<employee> emplist = new list<employee>()                         {                          new employee{age=15, name = "tom"},                          new employee{age=17, name = "billy"},                          new employee{age=25, name = "sam"}                         };  int maxvalue = emplist.select(i => i.age).max(); int index = emplist.findindex(t => t.age == maxvalue); 

but nested list

list<employee> emplist = new list<employee>()                     {                      new employee{age=15, name = "tom", new list<project>                      {                         id = 12, name = "project a",                         id = 11, name = "project b",                         id = 16, name = "project c"                      }},                      new employee{age=17, name = "billy",new list<project>                      {                         id = 17, name = "project d",                         id = 18, name = "project e",                         id = 10, name = "project f"                      }},                      new employee{age=25, name = "sam",new list<project>                      {                         id = 22, name = "project x",                         id = 24, name = "project y",                         id = 19, name = "project z"                      }}                     }; 

i know how max value of id have no idea how 2 indexes of it.

int maxvalue = emplist.selectmany(i => i.project).select(a => a.id).max(); 

the max value 24. want 2 indexes ( index 2 of employee , index 1 of project)

you can use overload of select projects index create anonymous type:

var maxitem = emplist    .select((emp, index) => new      {          maxproject = emp.project             .select((proj, pindex) => new{ proj, pindex })             .orderbydescending(x => x.proj.id)             .first(),         emp, index      })     .orderbydescending(x => x.maxproject.proj.id)     .first(); console.write("max-value:{0} emp-index:{1} project-index:{2}"     , maxitem.maxproject.proj.id     , maxitem.index      , maxitem.maxproject.pindex); 

(disclaimer: untested, presumes employees have non-empty list<employee> project)