File1 consist two columns, first some weired ids and second the numbers

Code:

t|v203.1@t|k88711.1	0.1
t|v190.1@t|k90369.1	0.01
t|v203.1@t|k88711.1	0.5
t|v322.1@t|k88711.1	0.2
t|v207.1@t|k90369.1	0.11
t|v326.1@t|k85939.1	0.5
t|v207.1@t|k90369.1	0.7
t|v207.1@t|k90369.1	0.3
t|v326.1@t|k89421.1	0.33

I want to add up the values of repeated ids and print 4 column File2
desired output File2

Code:

t|v203.1@t|k88711.1	0.1	0.1+0.5	0.6
t|v190.1@t|k90369.1	0.01	0.01	0.01
t|v322.1@t|k88711.1	0.2	0.2	0.2
t|v207.1@t|k90369.1	0.11	0.11+0.7+0.3	1.11
t|v326.1@t|k85939.1	0.5	0.5	0.5
t|v326.1@t|k89421.1	0.33	0.33	0.33

In the desired output file first and second columns are from file1, the third column shows what is going to be added for repeated ids, the fourth column is the values obtained by addition. The ids repeated will merge to one id as row 1 and 3 from File1 merged to row1 in File2.