# Interface problem

**URL:** <https://community.freefem.org/t/interface-problem/2739>\
**Category:** General Discussion\
**Created:** [October 5, 2023, 7:55am UTC](https://community.freefem.org/t/interface-problem/2739 "2023-10-05T07:55:07Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![junjie](https://avatars.discourse-cdn.com/v4/letter/j/278dde/32.png) [@junjie](https://community.freefem.org/u/junjie)\
**Post date:** [October 5, 2023, 7:55am UTC](https://community.freefem.org/t/interface-problem/2739/1 "2023-10-05T07:55:07Z")

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Hello everyone, I would like to ask if the interface problem can be solved in FreeFem? The true solution u is sharded. Like the numerical example shown in the picture below. If possible, can you send me an example? Grateful！

 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/e/edbb0a965136d83a936a323c90f0c7fff34ce67b.png)

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**Author:** ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)\
**Post date:** [October 6, 2023, 1:50pm UTC](https://community.freefem.org/t/interface-problem/2739/2 "2023-10-06T13:50:03Z")

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Yes, This is trivial

a first solution not validated

[PoissonJUmp.edp](https://community.freefem.org/uploads/short-url/7pVpNjJpP1xWjqq701MW819P2RC.edp) (395 Bytes)

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**Author:** ![junjie](https://avatars.discourse-cdn.com/v4/letter/j/278dde/32.png) [@junjie](https://community.freefem.org/u/junjie)\
**Post date:** [October 7, 2023, 2:58pm UTC](https://community.freefem.org/t/interface-problem/2739/3 "2023-10-07T14:58:32Z")

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Thank you very much for your reply！