Runtime error for practice problem Lucky Lucky Number

#include<stdio.h>
//#include<conio.h>
main()
{
int noc,n,near,a,b,i=0,l=1;;
scanf("%d",&noc);
outer: for(i=1;i<=noc;i++)
{
l=0;
scanf("%d",&n);
near=n-n%7;
//printf("%d\n",near);
a=near;
b=n-near;
//printf("%d %d\n",a,b);
while(a>=0)
{
if(b%4==0)
{
printf("%d\n",a);
l=1;
break;
}
a=a-7;
b=b+7;
}
if(l==0)
printf("-1\n");
}

      //getch();
}

What cud b the problem with above code? I m getting run-time error.
Practice problem Lucky Lucky Number.
Regards

Also, removed two semicolons in fifth line of code but same result

In C your method have to return int, add return 0 to the end of your code, read FAQ.

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