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Objectives: Find the shortest path in the Airline Network program using DFS algorithm

An unweighted digraph represented by its adjacency list is used for the network, and the information needed to construct is read from a network file.

Network file content:

Los$\_$Angeles

$3346$

San$\_$Francisco

$3134$

Denver

$3127$

Chicago

$238$

Boston

$246$

New$\_$York

$3478$

Miami

$3835$

New$\_$Orleans

$217$

Network file details

The order of cities are arranged from LA$(1),$ SAN$(2),$ DEN$(3),$ CHI$(4),$ BOS$(5),$ NYK$(6),$ MIA$(7),$ NOL$(8).$

First digit is the number of out$-$degrees; other digits are the destinations of out$-$degrees.

Sample outputAirline Map

Enter name of network file: c:

etworkfile.txt

The Digraph's Adjacency$-$List Representation:

$1$: Los$\_$Angeles$--346$

$2$: San$\_$Francisco$--134$

$3$: Denver$--123$

$4$: Chicago$--38$

$5$: Boston$--46$

$6$: New$\_$York$--478$

$7$: Miami$--835$

$8$: New$\_$Orleans$--17$

Number of start city? $1$

Number of destination? $2$

Shortest path from Los Angeles to San Francisco is:

$1$ Los$\_$Angeles

$|$

$$ v

$3$ Denver

$|$

$$ v

$2$ San$\_$Francisco

More $($Y or N$)?$Y

Number of start city? $6$

Number of destination? $4$

Shortest path from New York to Chicago is:

$6$ New$\_$York

$|$

$$ v

$4$ Chicago

More $($Y or N$)?$y