program that finds the intersection of two linked lists java
public class Solution {
static listnode headA,
headB;
static class listnode {
int data;
listnode next;
listnode(int d) {
data = d;
next = null;
}
}
int count(listnode head) {
int c = 0;
while (head != null) {
c++;
head = head.next;
}
return c;
}
int commonPoint(listnode headA, listnode headB) {
listnode p1 = headA;
listnode p2 = headB;
int c1 = count(headA);
int c2 = count(headB);
if (c1 > c2) {
for (int i = 0; i < c1 - c2; i++) {
if (p1 == null) {
return - 1;
}
p1 = p1.next;
}
}
if (c1 < c2) {
for (int i = 0; i < c2 - c1; i++) {
if (p2 == null) {
return - 1;
}
p2 = p2.next;
}
}
while (p1 != null && p2 != null) {
if (p1.data == p2.data) {
return p1.data;
}
p1 = p1.next;
p2 = p2.next;
}
return - 1;
}
public static void main(String[] args) {
Solution list = new Solution();
list.headA = new listnode(5);
list.headA.next = new listnode(4);
list.headA.next.next = new listnode(9);
list.headA.next.next.next = new listnode(7);
list.headA.next.next.next.next = new listnode(1);
list.headB = new listnode(6);
list.headB.next = new listnode(7);
list.headB.next.next = new listnode(1);
System.out.println(list.commonPoint(headA, headB));
}
}