Bits of .NET

String concatenation in loops creates tons of objects. StringBuilder is 100x faster.

❌ Slow (String Concat):

string result = "";
for (int i = 0; i < 10000; i++)
{
    result += i.ToString();  // Creates new string each time!
}
// 10,000 string objects created = slow + GC pressure

✅ Fast (StringBuilder):

var sb = new StringBuilder();
for (int i = 0; i < 10000; i++)
{
    sb.Append(i);
}
string result = sb.ToString();
// Single object modified = fast + minimal GC

Benchmark: String concat: 2000ms, StringBuilder: 15ms = 133x faster!