12239 solved

12239.cpp

@@ -0,0 +1,61 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+#define pow2(i) (1<<i)
+#define bit(i) (1<<i)
+#define isOdd(i) (i&1)
+#define isEven(i) (!(i&1))
+#define sz(i) i.size()
+#define REP(i, b, n) for (int i = b; i < n; i++)
+#define REPI(i, b, n) for (int i = b; i <= n; i++)
+#define rep(i, n) REP(i, 0, n)
+#define repi(i, n) REPI(i, 0, n)
+
+int abs(int a) {
+    return a < 0 ? -a : a;
+}
+
+int main(void) {
+    int n, b;
+    int ball;
+
+    while (cin >> n >> b) {
+        if (n == 0 && b == 0)
+            break;
+
+        vector<int> balls;
+
+        rep (i, b) {
+            cin >> ball;
+            balls.push_back(ball);
+        }
+
+        bool possible[n+1];
+
+        rep (i, n+1) {
+            possible[i] = false;
+        }
+
+        rep (i, b) {
+            rep (j, b) {
+                possible[abs(balls[i] - balls[j])] = true;
+            }
+        }
+
+        bool ok = true;
+        rep (i, n+1) {
+            if (possible[i] == false) {
+                ok = false;
+                break;
+            }
+        }
+
+        if (ok)
+            cout << "Y" << endl;
+        else
+            cout << "N" << endl;
+    }
+
+    return 0;
+}