visual basic c sharp bilen panpalarım yardm lazm

al amk dogrusuyla yap bari bunlardan yalan yanlis ogrenecegine
(null check, int kontrolu filan var)

using system;

namespace console
{
class program
{
static void main(string[] args)
{
string str1, str2, str3;
int i1, i2, i3;

do
{
console. write("1.yazılı notunu giriniz=");
str1 = console. readline();
} while (!((str1 != null) && int32.tryparse(str1, out i1)));

do
{
console. write("2.yazılı notunu giriniz=");
str2 = console. readline();
} while (!((str2 != null) && int32.tryparse(str2, out i2)));

do
{
console. write("3.yazılı notunu giriniz=");
str3 = console. readline();
} while (!((str3 != null) && int32.tryparse(str3, out i3)));

float ort = i1 + i2 + i3;
ort = ort/3;

console. write(ort > 50 ? "ortalaman {0} aferin gectin pic!" : "ortalaman {0} kaldin pic", ort);
console. readline();
}
}
}