source code pengecekan tanda kurung

#include "stdio.h"
#include "stdlib.h"

char kar[100];
char stack[100];
int top=-1;
char temp;
char xx;
int valid=1;

void main()
{

printf("Masukkan karakter=");
scanf("%s",&kar);

for(int i=0;i<=100;i++)
{
if(kar[i]=='{' || kar[i]=='(' || kar[i]=='[')
{
stack[top+1]=kar[i];
top++;
}
else if(kar[i]=='}' || kar[i]==')' || kar[i]==']')
{
temp=stack[top];stack[top]=NULL;top--;
if(temp=='{')
{ xx='}';}
else if(temp=='(')
{ xx=')';}
else if(temp=='[')
{ xx=']';}
if(xx!=kar[i])
{ valid=0;}
}
}
if(valid==1)
{
printf("\n\nVALID");
}else
{
printf("\n\nTDK VALID");
}
}