#include "iostream.h"
#include "stdio.h"
#include "math.h"
#include "COM_FG.h"
#include "define.h"

void COM_U(double U[4][N+3][M+3],double rfa,double Area[N+3][M+3],
		   double L_x[N+4][M+3],double L_y[N+4][M+3],double H_x[N+3][M+4],double H_y[N+3][M+4])
{
		double F[4][N+3][M+4],G[4][N+4][M+3],R[4][N+3][N+3],dt[1];
		int i,j,n;

		COM_FG(U,F,G,dt,Area,L_x,L_y,H_x,H_y);

		for(i=2;i<N+1;i++)
			for(j=2;j<M+1;j++)
			{
				for(n=0;n<4;n++)
				{
					R[n][i][j]=(F[n][i][j+1]-F[n][i][j])+(G[n][i+1][j]-G[n][i][j]);
					U[n][i][j]=U[n][i][j]-rfa*dt[0]*R[n][i][j]/Area[i][j];					
				}
			}
}