sum square difference

sum_square_difference/main.go

@@ -0,0 +1,23 @@
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("sum square difference of 100 is", SquareSum(100)-SumOfSquares(100))
+}
+
+func SquareSum(n int) int {
+	var sum int
+	for i := 1; i <= n; i++ {
+		sum += i
+	}
+	return sum * sum
+}
+
+func SumOfSquares(n int) int {
+	var sum int
+	for i := 1; i <= n; i++ {
+		sum += i * i
+	}
+	return sum
+}

sum_square_difference/sum_square_difference_test.go

@@ -0,0 +1,69 @@
+package main
+
+import "testing"
+
+func TestSumOfSquares(t *testing.T) {
+	tt := []struct {
+		name  string
+		input int
+		want  int
+	}{
+		{
+			"1",
+			1,
+			1,
+		},
+		{
+			"10",
+			10,
+			385,
+		},
+		{
+			"5",
+			5,
+			1 + 4 + 9 + 16 + 25,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := SumOfSquares(tc.input)
+			if got != tc.want {
+				t.Errorf("SumOfSquares(%d)=%d, want %d", tc.input, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestSquareSum(t *testing.T) {
+	tt := []struct {
+		name  string
+		input int
+		want  int
+	}{
+		{
+			"1",
+			1,
+			1,
+		},
+		{
+			"5",
+			5,
+			15 * 15,
+		},
+		{
+			"10",
+			10,
+			3025,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := SquareSum(tc.input)
+			if got != tc.want {
+				t.Errorf("SquareSum(%d)=%d, want %d", tc.input, got, tc.want)
+			}
+		})
+	}
+}