Update 24.4.md

Author: sta314

docs/Chap24/24.4.md

@@ -75,7 +75,7 @@ No, it cannot be positive. This is because for every vertex $v \ne v_0$, there i
 
 > Show how to modify the Bellman-Ford algorithm slightly so that when we use it to solve a system of difference constraints with $m$ inequalities on $n$ unknowns, the running time is $O(nm)$.
 
-We can follow the advice of problem 14.4-7 and solve the system of constraints on a modified constraint graph in which there is no new vertex $v_0$. This is simply done by initializing all of the vertices to have a $d$ value of $0$ before running the iterated relaxations of Bellman Ford. Since we don't add a new vertex and the $n$ edges going from it to to vertex corresponding to each variable, we are just running Bellman Ford on a graph with $n$ vertices and $m$ edges, and so it will have a runtime of $O(mn)$.
+We can follow the advice of problem 24.4-7 and solve the system of constraints on a modified constraint graph in which there is no new vertex $v_0$. This is simply done by initializing all of the vertices to have a $d$ value of $0$ before running the iterated relaxations of Bellman Ford. Since we don't add a new vertex and the $n$ edges going from it to to vertex corresponding to each variable, we are just running Bellman Ford on a graph with $n$ vertices and $m$ edges, and so it will have a runtime of $O(mn)$.
 
 ## 24.4-6