Plot a histogrm from multiple txt files

how we can plot a histogram from columns in 2 different txt files using root

If you have one column in your files, try the macro: Read txt file and draw histogram
and replace:
t->ReadFile(“a.txt”, “v/D”);
with two lines:
t->ReadFile(“FirstFile.txt”, “v/D”);

If you have two columns in your files, try: TTree *t = new TTree("t", "a tree"); t->ReadFile("FirstFile.txt", "x/D:y"); t->ReadFile("SecondFile.txt"); t->Draw("y:x");

@Pepe Le Pew thank you for replying , still
i tried the code you write and gives me “Warning in TTree::ReadStream: Ignoring trailing " 0.014999999999999999 150” while reading line 1 " for all lines in txt file
i have 3 column for each the 2 txt file and i need to specify a column from each one how can i do this

t->ReadFile(“FirstFile.txt”, “x/D:y:z”);