diff --git "a/\354\247\200\354\235\200/boj/13458.cpp" "b/\354\247\200\354\235\200/boj/13458.cpp"
new file mode 100644
index 0000000..f77e814
--- /dev/null
+++ "b/\354\247\200\354\235\200/boj/13458.cpp"
@@ -0,0 +1,34 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+int main() {
+	ios_base::sync_with_stdio(false);
+	cin.tie(NULL);
+
+	long long answer = 0;
+	int n, b, c;
+	cin >> n;
+
+	vector<int> a(n);
+	for (int i = 0; i < n; i++)
+		cin >> a[i];
+
+	cin >> b >> c;
+
+	for (int i = 0; i < n; i++) {
+		a[i] -= b;
+		answer++;
+
+		if (a[i] > 0) {
+			answer += a[i] / c;
+			if (a[i] % c != 0) {
+				answer++;
+			}
+		}
+	}
+
+	cout << answer;
+
+	return 0;
+}
\ No newline at end of file
diff --git "a/\354\247\200\354\235\200/boj/1987.cpp" "b/\354\247\200\354\235\200/boj/1987.cpp"
new file mode 100644
index 0000000..19de419
--- /dev/null
+++ "b/\354\247\200\354\235\200/boj/1987.cpp"
@@ -0,0 +1,50 @@
+#include <iostream>
+#include <string>
+#include <algorithm>
+using namespace std;
+
+int r, c, answer;
+int dx[] = { 1,0,-1,0 };
+int dy[] = { 0,1,0,-1 };
+char board[20][20];
+bool alphabet[26];
+
+void dfs(int cnt, int y, int x) {
+	for (int i = 0; i < 4; i++) {
+		int next_y = y + dy[i];
+		int next_x = x + dx[i];
+
+		if (next_y < 0 || next_y >= r || next_x < 0 || next_x >= c)
+			continue;
+
+		if (!alphabet[board[next_y][next_x] - 'A']) {
+			alphabet[board[next_y][next_x] - 'A'] = true;
+
+			dfs(cnt + 1, next_y, next_x);
+
+			alphabet[board[next_y][next_x] - 'A'] = false;
+		}
+	}
+
+	if (answer < cnt)
+		answer = cnt;
+}
+
+int main() {
+	cin >> r >> c;
+
+	for (int i = 0; i < r; i++) {
+		string str;
+		cin >> str;
+		for (int j = 0; j < str.size(); j++) {
+			board[i][j] = str[j];
+		}
+	}
+
+	alphabet[board[0][0] - 'A'] = true;
+	dfs(1, 0, 0);
+
+	cout << answer;
+
+	return 0;
+}
\ No newline at end of file