solve for smallest n

2 files changed, 63 insertions, 0 deletions

diff --git a/exercises/1.2-3/main.go b/exercises/1.2-3/main.go
new file mode 100644
index 0000000..8abbbb9
--- /dev/null
+++ b/exercises/1.2-3/main.go
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+func main() {
+	fmt.Println("n,100n^2,2^n")
+
+	for n := 1.0; n < 100; n++ {
+		x := 100 * math.Pow(n, 2)
+		y := math.Pow(2, n)
+
+		fmt.Printf("%v,%v,%v\n", n, x, y)
+
+		if x < y {
+			break
+		}
+	}
+}
diff --git a/notes.md b/notes.md
index f21eb7e..3b94338 100644
--- a/notes.md
+++ b/notes.md
@@ -159,3 +159,45 @@ insertion sort beat merge sort?
     43,14792,14933.080604940173
     44,15488,15373.759438082629
     ```
+
+1.2-3: What is the smallest value of `n` such that an algorithm whose running
+time is 100n^2 runs faster than an algorithm whose running time is 2^n on the
+same machine?
+
+    15. Calculated using:
+
+    ```golang
+    func main() {
+      fmt.Println("n,100n^2,2^n")
+
+      for n := 1.0; n < 100; n++ {
+        x := 100 * math.Pow(n, 2)
+        y := math.Pow(2, n)
+
+        fmt.Printf("%v,%v,%v\n", n, x, y)
+
+        if x < y {
+          break
+        }
+      }
+    }
+    ```
+
+    ```csv
+    n,100n^2,2^n
+    1,100,2
+    2,400,4
+    3,900,8
+    4,1600,16
+    5,2500,32
+    6,3600,64
+    7,4900,128
+    8,6400,256
+    9,8100,512
+    10,10000,1024
+    11,12100,2048
+    12,14400,4096
+    13,16900,8192
+    14,19600,16384
+    15,22500,32768
+    ```