55: lychrel numbers

55_lychrel_numbers/main.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"math/big"
+	"strings"
+)
+
+func main() {
+
+}
+
+func isLychrelNumber(n int) bool {
+	return false
+}
+
+func IsPalindrome(n *big.Int) bool {
+	str := n.String()
+	pb := strings.Builder{}
+	for i := len(str); i > 0; i-- {
+		pb.WriteString(str[i-1 : i])
+	}
+	pstr := pb.String()
+	return str == pstr
+}

55_lychrel_numbers/main_test.go

@@ -0,0 +1,66 @@
+package main
+
+import (
+	"math/big"
+	"testing"
+)
+
+func TestIsPalindrome(t *testing.T) {
+	fn, _ := (&big.Int{}).SetString("10203040506070809", 0)
+	fn2, _ := (&big.Int{}).SetString("1234567890987654321", 0)
+	type args struct {
+		n *big.Int
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			"test1",
+			args{fn},
+			false,
+		},
+		{
+			"test2",
+			args{fn2},
+			true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := IsPalindrome(tt.args.n); got != tt.want {
+				t.Errorf("IsPalindrome() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_isLychrelNumber(t *testing.T) {
+	type args struct {
+		n int
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			"test1",
+			args{47},
+			true,
+		},
+		{
+			"test1",
+			args{4994},
+			false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isLychrelNumber(tt.args.n); got != tt.want {
+				t.Errorf("isLychrelNumber() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}