diff --git a/b.py b/b.py
new file mode 100644
index 0000000..3fa9d74
--- /dev/null
+++ b/b.py
@@ -0,0 +1,9 @@
+from __future__ import print_function
+import sys
+
+n, m  = map(int, sys.stdin.readline().split())
+M     = [ map(int, line.split()) for line in sys.stdin ]
+S     = set()
+
+for i, j in M:
+  
diff --git a/h.py b/h.py
new file mode 100644
index 0000000..63db134
--- /dev/null
+++ b/h.py
@@ -0,0 +1,45 @@
+from __future__ import print_function
+import sys, math
+
+def val(c,f,u):
+  a, b = c - min(c, f), f - min(c, f)
+  if u > b - a:
+    return b + (lambda x: x//2+1 if x%2==0 and x!=0 else int(math.ceil(x/2.0)))(u - b)
+  else:
+    return None
+
+s = int(sys.stdin.readline())
+D = []
+n = 0
+
+for d,c,f,u in ( map(int, line.split()) for line in sys.stdin ):
+  n += d; x = val(c,f,u)
+  if x is not None: D.append((d,x))
+
+# print(D)
+
+m     = n//2+1
+C     = [ [0,set()] for i in xrange(n+1) ]
+
+for i in xrange(n+1):
+  xs = [ (C[i-D[j][0]], j, D[j][1]) for j in xrange(len(D)) 
+           if D[j][0] <= i and j not in C[i-D[j][0]][1] ]
+  # print("i = ", i, " xs = ", xs)
+  if xs:
+    c, j, cost = min(xs, key = lambda x: x[2])
+    C[i] = c[:]
+    C[i][0] += cost
+    C[i][1] = C[i][1].copy(); C[i][1].add(j)
+  else:
+    C[i] = C[i-1]
+  # print(C[i])
+
+# print(m, n)
+# for c in C: print(c)
+
+for i in xrange(n+1):
+  cost, delegates = sum( D[j][1] for j in C[i][1] ), sum( D[j][0] for j in C[i][1] )
+  if delegates >= m:
+    print(cost)
+    sys.exit(0)
+print("impossible")