Developing an efficient parallel numerical integration program on a $2-$D mesh, as described in textbook Chapter $8$ Programming Projects, page $302.$

I have the following C$*($cstar$)$ code for this project and it's compiling without issue, but when I try to run it my environment crashes:

$/*$ Parallel Numerical Integration Program $*/$

#include

#include

#define numproc $40$

#define numpoints $30$

#define N $6$

int MESH$\_$DIM $=($int$)$sqrt$($numproc$)$;

float a $=0\mathrm{.}0,$ b $=2\mathrm{.}0,$ w$,$ globalsum $=0\mathrm{.}0,$ answer;

spinlock L;

float local$\_$sums$[$N$][$N$]$;

int i$,$ j$,$ row, col;

float f$($float t$)\{$

$$ return sqrt$(4-$ t $*$ t$)$;

$\}$

void Integrate$($int myrow, int mycol$)\{$

$$ float localsum $=0\mathrm{.}0$;

$$ float t;

$$ int x;

$$ int myindex $=$ myrow $*$ MESH$\_$DIM $+$ mycol;

$$ t $=$ a $+$ myindex $*($b $-$ a$)/$ numproc;

$$

$$ for $($x $=1$; x $<=$ numpoints; x$++)\{$

$$ localsum $+=$ f$($t$)$;

$$ t $+=$ w;

$\}$

$$ localsum $=$ w $*$ localsum;

$$ local$\_$sums$[$myrow$][$mycol$]=$ localsum;

$\}$

void meshReduceSum$()\{$

$$ for $($row $=0$; row $<$ MESH$\_$DIM; row$++)\{$

$$ for $($col $=1$; col $<$ MESH$\_$DIM; col$++)\{$

$$ local$\_$sums$[$row$][0]+=$ local$\_$sums$[$row$][$col$]$;

$\}$

$\}$

$$ for $($row $=1$; row $<$ MESH$\_$DIM; row$++)\{$

$$ local$\_$sums$[0][0]+=$ local$\_$sums$[$row$][0]$;

$\}$

$$ globalsum $=$ local$\_$sums$[0][0]$;

$\}$

main$()\{$

$$ w $=($b $-$ a$)/($numproc $*$ numpoints$)$;

$$

$$ forall i $=0$ to MESH$\_$DIM do

$$ forall j $=0$ to MESH$\_$DIM do

$$ Integrate$($i$,$ j$)$;

$$ meshReduceSum$()$;

$$ answer $=$ globalsum $+$ w $/2*($f$($b$)-$ f$($a$))$;

$$ cout $<<$ "Approximation to the value of pi: $\%$f

$"<<$ answer;

$$ return $0$;

$\}$