diff --git "a/khj20006/202510/21 BOJ P4 \352\262\275\353\241\234 \354\210\230\354\240\225\355\225\230\352\270\260.md" "b/khj20006/202510/21 BOJ P4 \352\262\275\353\241\234 \354\210\230\354\240\225\355\225\230\352\270\260.md"
new file mode 100644
index 00000000..ec78cad7
--- /dev/null
+++ "b/khj20006/202510/21 BOJ P4 \352\262\275\353\241\234 \354\210\230\354\240\225\355\225\230\352\270\260.md"	
@@ -0,0 +1,32 @@
+```cpp
+#include <bits/stdc++.h>
+using namespace std;
+
+int N, Q;
+int U = 0, D = 0, L = 0, R = 0, X = 0, Y = 0;
+
+int main() {
+	cin.tie(0)->sync_with_stdio(0);
+
+	cin >> N >> Q;
+	for (int i = 0; i < N; i++) {
+		char a;
+		cin >> a;
+		if (a == 'U') U++, Y++;
+		if (a == 'D') D++, Y--;
+		if (a == 'L') L++, X--;
+		if (a == 'R') R++, X++;
+	}
+
+	for (int x, y; Q--;) {
+		cin >> x >> y;
+		int xDiff = abs(x - X), yDiff = abs(y - Y);
+		if (abs(x) + abs(y) > N || (x + y) % 2 != (X + Y) % 2) {
+			cout << "-1\n";
+			continue;
+		}
+		cout << (xDiff + yDiff) / 2 << '\n';
+	}
+
+}
+```