How do you write a program in c plus plus that implements the n-queens problem with backtracking?

#include<stdio.h>

#include<conio.h>

#include<math.h>

int a[30],count=0;

int place(int pos)

{

int i;

for(i=1;i<pos;i++)

{

if((a[i]==a[pos])((abs(a[i]-a[pos])==abs(i-pos))))

return 0;

}

return 1;

}

void print_sol(int n)

{

int i,j;

count++;

printf("\n\nSolution #%d:\n",count);

for(i=1;i<=n;i++)

{

for(j=1;j<=n;j++)

{

if(a[i]==j)

printf("Q\t");

else

printf("*\t");

}

printf("\n");

}

}

void queen(int n)

{

int k=1;

a[k]=0;

while(k!=0)

{

a[k]=a[k]+1;

while((a[k]<=n)&&!place(k))

a[k]++;

if(a[k]<=n)

{

if(k==n)

print_sol(n);

else

{

k++;

a[k]=0;

}

}

else

k--;

}

}

void main()

{

int i,n;

clrscr();

printf("Enter the number of Queens\n");

scanf("%d",&n);

queen(n);

printf("\nTotal solutions=%d",count);

getch();

}