stack.c

bool isValid(char* s) {
    int stack[10000];
    int top=-1;

    for(int i = 0; i < strlen(s); i++)
    {
        switch(s[i])
        {
            case '(' : stack[++top] = 1;
                       continue;
            case '{' : stack[++top] = 2;
                       continue;
            case '[' : stack[++top] = 3;
                       continue;
            case ')' : if (top <0 || stack[top] != 1)
                        return false;
                       else
                        top--;
                       continue;
            case '}' : if (top < 0 || stack[top] != 2)
                        return false;
                       else
                        top--;
                       continue;
            case ']' : if (top < 0 || stack[top] != 3)
                        return false;
                       else
                        top--;
                       continue;
        }
    }
    return (top==-1);
}