# On the addition of two mesh

**URL:** <https://community.freefem.org/t/on-the-addition-of-two-mesh/2129>\
**Category:** General Discussion\
**Created:** [November 19, 2022, 11:59am UTC](https://community.freefem.org/t/on-the-addition-of-two-mesh/2129 "2022-11-19T11:59:07Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Yangshen](https://avatars.discourse-cdn.com/v4/letter/y/838e76/32.png) [@Yangshen](https://community.freefem.org/u/Yangshen)\
**Post date:** [November 19, 2022, 11:59am UTC](https://community.freefem.org/t/on-the-addition-of-two-mesh/2129/1 "2022-11-19T11:59:07Z")

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Hello everyone,  
I generated the following model.

 ![图片](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/9/9d85404f590a969870b6be64bfa291fa46929ad1.png)

It is composed of two meshes, Sh3 and Th3. The code is as follows.  
load"msh3"  
load"iovtk"  
load"medit"  
mesh Sh=square(48,12,[200_x,50_y]);  
mesh Th=square(48,12,[100_x,20_y]);  
Th=movemesh(Th,[x+50,y+15]);  
mesh3 Sh3=buildlayers(Sh,3,zbound=[0,-1]);  
mesh3 Th3=buildlayers(Th,3,zbound=[0,1]);  
mesh3 Zh=Sh3+Th3;  
//Sh3=buildmesh(mesh3);  
medit(“Al”,Zh);

I want to know the meaning of this code

mesh3 Zh=Sh3+Th3; I guess this code glues the Sh3 and Th3 grids together like glue, right?  
I want to know the meaning of this code  
mesh3 Zh=Sh3+Th3; I guess this code glues the Sh3 and Th3 grids together, right?  
In addition, how to define the label of the newly generated grid Zh?  
Thank you.