Project Euler - Problem 1 solution

project_euler/problem_1/problem1.go

@@ -0,0 +1,23 @@
+/**
+ * Problem 1 - Multiples of 3 and 5
+ *
+ * @see {@link https://projecteuler.net/problem=1}
+ *
+ * If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
+ * Find the sum of all the multiples of 3 or 5 below 1000.
+ *
+ * @author ddaniel27
+ */
+package problem_1
+
+func Problem1(n uint) uint {
+	sum := uint(0)
+
+	for i := uint(1); i < n; i++ {
+		if i%3 == 0 || i%5 == 0 {
+			sum += i
+		}
+	}
+
+	return sum
+}

project_euler/problem_1/problem1_test.go

@@ -0,0 +1,49 @@
+package problem_1_test
+
+import (
+	"testing"
+
+	"github.com/TheAlgorithms/Go/project_euler/problem_1"
+)
+
+// Tests
+func TestProblem1_Func(t *testing.T) {
+	tests := []struct {
+		name      string
+		threshold uint
+		want      uint
+	}{
+		{
+			name:      "Testcase 1 - threshold 10",
+			threshold: 10,
+			want:      23,
+		},
+		{
+			name:      "Testcase 2 - threshold 100",
+			threshold: 100,
+			want:      2318,
+		},
+		{
+			name:      "Testcase 3 - threshold 1000",
+			threshold: 1000,
+			want:      233168,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			n := problem_1.Problem1(tt.threshold)
+
+			if n != tt.want {
+				t.Errorf("Problem1() = %v, want %v", n, tt.want)
+			}
+		})
+	}
+}
+
+// Benchmarks
+func BenchmarkProblem1(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		_ = problem_1.Problem1(1000)
+	}
+}