The lastIndexOf() method of Longs Class in Guava library is used to find the last index of the given long value in a long array. This long value to be searched and the long array in which it is to be searched, both are passed as a parameter to this method. It returns an integer value which is the last index of the specified long value. If the value is not found, it returns -1.
Syntax:
public static int lastIndexOf(long[] array, long target)
Parameters: This method accepts two mandatory parameters:
- array: which is the array of long values in which the long value is to searched.
- target: which is long value to be searched for last index in the long array.
Return Value: This method returns an integer value which is the last index of the specified long value. If the value is not found, it returns -1.
Below programs illustrates this method:
Example 1:
// Java code to show implementation of // Guava's Longs.lastIndexOf() method import com.google.common.primitives.Longs; import java.util.Arrays; class GFG { // Driver's code public static void main(String[] args) { // Creating a long array long [] arr = { 1 , 2 , 3 , 4 , 3 , 5 , 3 , 4 }; long target = 3 ; // Using Longs.lastIndexOf() method // to get the index of last appearance // of a given element in array // and return -1 if element is // not found in the array int index = Longs.lastIndexOf(arr, target); if (index != - 1 ) { System.out.println( "Target is present" + " at index " + index); } else { System.out.println( "Target is not present" + " in the array" ); } } } |
Target is present at index 6
Example 2:
// Java code to show implementation of // Guava's Longs.lastIndexOf() method import com.google.common.primitives.Longs; import java.util.Arrays; class GFG { // Driver's code public static void main(String[] args) { // Creating a long array long [] arr = { 3 , 5 , 7 , 11 , 13 }; long target = 17 ; // Using Longs.lastIndexOf() method // to get the index of last appearance // of a given element in array // and return -1 if element is // not found in the array int index = Longs.lastIndexOf(arr, target); if (index != - 1 ) { System.out.println( "Target is present" + " at index " + index); } else { System.out.println( "Target is not present" + " in the array" ); } } } |
Target is not present in the array
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