CODEWITHSUNDEEP
javaarraysstringif-statement
user3479194
user3479194

Reputation: 1

How to check equal Names in String Array in Java?

I have an array (temp3) of names.

I need determine if any name is equal to another name in the array, without repeating comparisons.

This is what I have so far, thanks.

for(int m=0; m<3; m++){
    for(int n=0; n<3; n++){
        if(m!=n){
            if(temp3[m]==temp3[n]){
                System.out.println("Yes");
        }
      }
   }
}

Upvotes: 0

Views: 1781

Answers (3)

DaoWen
DaoWen

Reputation: 33029

You could also do this without any explicit looping by using a Set:

if (temp3.length != new HashSet<String>(Arrays.asList(temp3)).size()) {
    System.out.println("Yes");
}

This works by checking if the final Set has the same number of entries as the array. If not, then there must have been a duplicate. (This is actually an instance of the Pigeonhole Principle. I find it kind of funny that such a simple deduction needs a special name!)

Upvotes: 0

cybersam
cybersam

Reputation: 67019

This is a faster solution. We do not repeat any comparisons, and we automatically avoid comparing a string to itself.

for (int i=0; i< strings.length;i++) {
  for (int j= i + 1; j<strings.length;j++) {
     if (strings[i].equals(strings[j]))
        System.out.println("The two strings are the same");
   }
}

Upvotes: 1

CMPS
CMPS

Reputation: 7769

for(int i=0; i< strings.length;i++){        // Pick a string
  for(int j=i+1; j<strings.length;j++){       // Loop on all strings starting from i+1
         if(strings[i].equals(strings[j]))  // check if the two strings are equal
            System.out.println("The two strings are the same"); // SOP
      }
   }
}

Upvotes: 1

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