/*--- Local variables ---*/

int KindElem, KindBound;

int iElem, nNode, mNode;

int iNode, jNode, nPoint, iPoint, jPoint, kPoint;

ofstream Mesh_File;

/*--- Set the VTK type for the interior elements and the boundary elements ---*/

KindElem = 5; // Triangle

KindBound = 3; // Line

/*--- Store the number of nodes and output mesh filename ---*/

nNode = 3;

mNode = 3;

/*--- Open .su2 grid file ---*/

Mesh_File.precision(15);

Mesh_File.open("square.su2", ios::out);

/*--- Write the dimension of the problem and the number of interior elements ---*/

Mesh_File << "%" << endl;

Mesh_File << "% Problem dimension" << endl;

Mesh_File << "%" << endl;

Mesh_File << "NDIME= 2" << endl;

Mesh_File << "%" << endl;

Mesh_File << "% Inner element connectivity" << endl;

Mesh_File << "%" << endl;

Mesh_File << "NELEM= " << 2*(nNode-1)*(mNode-1) << endl;

/*--- Write the element connectivity ---*/

iElem = 0;

for (jNode = 0; jNode < mNode-1; jNode++) {

for (iNode = 0; iNode < nNode-1; iNode++) {

iPoint = jNode*nNode + iNode;

jPoint = jNode*nNode + iNode + 1;

kPoint = (jNode + 1)*nNode + iNode;

Mesh_File << KindElem << "\t" << iPoint << "\t" << jPoint << "\t" << kPoint << "\t" << iElem << endl;

iElem ++;

iPoint = jNode*nNode + (iNode + 1);

jPoint = (jNode + 1)*nNode + (iNode + 1);

kPoint = (jNode + 1)*nNode + iNode;

Mesh_File << KindElem << "\t" << iPoint << "\t" << jPoint << "\t" << kPoint << "\t" << iElem << endl;

iElem++;

}

}

/*--- Compute the number of nodes and write the node coordinates ---*/

nPoint = (nNode)*(mNode);

Mesh_File << "%" << endl;

Mesh_File << "% Node coordinates" << endl;

Mesh_File << "%" << endl;

Mesh_File << "NPOIN= " << nNode*mNode << endl;

iPoint = 0;

for (jNode = 0; jNode < mNode; jNode++) {

for (iNode = 0; iNode < nNode; iNode++) {

Mesh_File << ((double)iNode)/((double)(nNode-1)) << "\t" << ((double)jNode)/((double)(mNode-1)) << "\t" << iPoint << endl;

iPoint++;

}

}

/*--- Write the header information for the boundary markers ---*/

Mesh_File << "%" << endl;

Mesh_File << "% Boundary elements" << endl;

Mesh_File << "%" << endl;

Mesh_File << "NMARK= 4" << endl;

/*--- Write the boundary information for each marker ---*/

Mesh_File << "MARKER_TAG= lower" << endl;

Mesh_File << "MARKER_ELEMS= "<< (nNode-1) << endl;

for (iNode = 0; iNode < nNode-1; iNode++) {

Mesh_File << KindBound << "\t" << iNode << "\t" << (iNode + 1) << endl;

}

Mesh_File << "MARKER_TAG= right" << endl;

Mesh_File << "MARKER_ELEMS= "<< (mNode-1) << endl;

for (jNode = 0; jNode < mNode-1; jNode++) {

Mesh_File << KindBound << "\t" << jNode*nNode + (nNode - 1) << "\t" << (jNode + 1)*nNode + (nNode - 1) << endl;

}

Mesh_File << "MARKER_TAG= upper" << endl;

Mesh_File << "MARKER_ELEMS= "<< (nNode-1) << endl;

for (iNode = 0; iNode < nNode-1; iNode++) {

Mesh_File << KindBound << "\t" << (nNode*mNode - 1) - iNode << "\t" << (nNode*mNode - 1) - (iNode + 1) << endl;

}

Mesh_File << "MARKER_TAG= left" << endl;

Mesh_File << "MARKER_ELEMS= "<< (mNode-1) << endl;

for (jNode = mNode-2; jNode > mNode-4; jNode--) {

Mesh_File << KindBound << "\t" << (jNode + 1)*nNode << "\t" << jNode*nNode << endl;

}

/*--- Close the mesh file and exit ---*/

Mesh_File.close();

return 0;