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Java: Concatenation

We already know about the mathematical operation of addition. Such a program:

System.out.print(5 + 3);

will display 8 - the result of the binary operator + with the operands 5 and 3.

Above the strings defined their operations. You can "fold" two lines. Such a program:

System.out.print("Dragon" + "stone");

will display Dragonstone - the result of the binary operator + with the 'Dragon' and 'stone' operands.

This operation is called concatenation. Roughly speaking, this is the "gluing" of the lines. Gluing always happens in the same order in which the operands are written, in other words, the left operand becomes the left part of the string, and the right operand becomes the left.

Here are some more examples:

System.out.print("Kings" + "wood");     // => Kingswood

System.out.print("Kings" + "road");     // => Kingsroad

System.out.print("King's" + "Landing"); // => King'sLanding

In the last example, the name of the city turned out to be with an error: King's Landing must be written with a space! But there were no spaces in our initial lines, and the spaces in the code to the left and right of the + character do not matter, because they are not part of the lines.

Let's try to solve this problem in different ways:

System.out.print("King's " + "Landing");      //  => King's Landing

System.out.print("King's" + " Landing");      //  => King's Landing

System.out.print("King's" + " " + "Landing"); //  => King's Landing

A space is the same character as the others, therefore, how many spaces to put in a line will be as much:

System.out.print("King's " + " Landing");   // => King's  Landing

System.out.print("King's  " + "  Landing"); // => King's    Landing



Winter came for the House of Frey.

using concatenation of words. Each word must be represented in a separate line. Do not forget about the spaces.

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