Change default sieve size to 10485760.

I don't know why yet, but this seems to be the near optimal sieve size
when testing with the benchmarking script. It's equal to `1024^2 * 10`.

benchmark.sh

@@ -1,9 +1,10 @@
 #!/bin/bash
 
-BIN="./target/release/indivisible"
+EXE="./target/release/indivisible"
+OPTIONS=()
 TRIALS=20
 
-if ! [ -f "$BIN" ]
+if ! [ -f "$EXE" ]
 then
 	>&2 echo "Release build not available. Please run 'cargo build -r'."
 	exit 1
@@ -15,11 +16,27 @@ then
 	exit 1
 fi
 
-echo "Calculating primes up to 100,000,000"
+while getopts "t:s:" opt
+do
+	case "$opt" in
+		s)
+			OPTIONS=("${OPTIONS[@]}" -s "$OPTARG")
+			;;
+		t)
+			TRIALS="$OPTARG"
+			;;
+		*)
+			>&2 echo "Uknown option $opt"
+			exit 1
+			;;
+	esac
+done
+
+echo "Calculating primes up to 1,000,000,000"
 TOTAL="0"
 for _ in $(seq "$TRIALS")
 do
-	TIME=$(command time -f "%e" "$BIN" 100000000 2>&1 >/dev/null)
+	TIME=$(command time -f "%e" "$EXE" "${OPTIONS[@]}" 1000000000 2>&1 >/dev/null)
 	TOTAL=$(calc "$TOTAL + $TIME")
 done
 

src/main.rs

@@ -35,7 +35,7 @@ struct Opt {
 	test:bool,
 	#[structopt(help = "Max of the prime to generate or number to test for primality")]
 	num:usize,
-	#[structopt(short, long, name = "SIZE", default_value = "1000", help = "Set a custom sieve size")]
+	#[structopt(short, long, name = "SIZE", default_value = "10485760", help = "Set a custom sieve size")]
 	sieve:usize,
 	//#[structopt(short, long, name = "n", default_value = "1", help = "Number of threads to spawn")]
 	//jobs:u64,