C# - why is this program giving me an error? -

i practicing programming exam , that's 1 of exams. program crashes after first loop , can't figure out why. please help!

    int n = int.parse(console.readline());      console.writeline("{0}{1}{0}", new string('-', n / 2), new string('*', n + 2));      (int = 0; < n - 1; i++)     {         console.writeline("{0}*{1}*{0}", new string('-', n / 2), new string('-', n));     }      (int = 0; < n; i++)     {         console.writeline(             "{0}{1}{2}{1){0}",             new string('-', ((n - 1) / 2) - i),             new string('*', 1 + 2 * i),             new string('-', n - 2 * i));          if (i < n / 2)         {             i++;         }         else         {             i--;         }     } 

"{0}{1}{2}{1){0}", 

your string format error,you need change {1) {1},but seems code never end while input 5! , other input take exception,can explain want ?

"{0}{1}{2}{1}{0}", 

i changed code method now

static void printdemo(int num) {     if (num < 0 || num % 2 == 0)     {         return;//do nothing     }     console.writeline("{0}{1}{0}", new string('-', num / 2), new string('*', num + 2));      (int = 0; < num - 1; i++)     {         console.writeline("{0}*{1}*{0}", new string('-', num / 2), new string('-', num));     }      (int = 0; < num; i++)     {         var t1 = math.abs(num / 2 - i);         var t2 = t1 * 2 + 1;         var t3 = (num * 2 + 1 - t1 * 2 - t2) / 2;         console.writeline(             "{0}{1}{2}{1}{0}",             new string('-', t1),             new string('*', t3),             new string('-', t2));     } }