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Solved: The index 1 is out of range.

This error usually comes when we try to insert data in a query where there is no index defined for it. Example :- String strQuery=“select * from location where city_id=? ”; The question mark will be the the first index if we want to insert data so if we call a function like- oPreparedStatement = oConnection.prepareStatement(strQuery); oPreparedStatement.setString(1,235); here we are sending 235 as a first parameter so it will work fine but as soon as we write something after it like oPreparedStatement.setString(2,”kanpur”) then it will throw “The index 2 is out of range” since there is no place to send this value in a query hence it will throw the same error. Here index defines the parameter for which there is no place in the query. To rectify this we need to write query like- String strQuery=“select * from location where city_id=? And city_name=? ”; then it will work fine. The cases in which these errors can occur is- 1)Query is co

Shortest Path from source to Vertex :- Dijkstra Algorithm

Shortest Path from source to Vertex :- Dijkstra Algorithm:- Dijkstra  Algorithms is an algorithm use to find the shortest path from source vertex to a given vertex. package Graph ; import java.util.HashMap ; abstract public class DirectedGraph { Vertex [] vertexlist = new Vertex [ 10 ]; HashMap < Character , HashMap < Character , Integer >> edgelist = new HashMap <>(); Vertex vertex ; //count of vertex and edge static int vertexcount = 0 ; int edgecount = 0 ; /* * This function takes a label and insert in the vertex list as well as edge list since it is new vertex it will add * null to its adjoining vertices */ int addVertex ( char label ) { vertex = new Vertex ( label ); vertexlist [ vertexcount ]= vertex ; System . out . println ( vertexlist [ vertexcount ]. label ); edgelist . put ( vertex . label , null ); vertexcount ++; return vertexcount ; } int addEdge ( char label , char []