Merge pull request #50 from julienc/master

Fix 'weight' -> 'value' in Knapsack solution 2

chapter07.tex

@@ -683,7 +683,7 @@ using the following sequence:
 denote the smallest possible total weight
 when a subset of objects
 $1 \ldots k$ is selected such
-that the total weight is $u$.
+that the total value is $u$.
 The solution to the problem is the
 largest value $u$
 for which  $0 \le u \le s$ and $f(n,u) \le x$