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Check if two given circles touch or intersect each other
• Difficulty Level : Easy
• Last Updated : 29 Apr, 2021

There are two circle A and B with their centers C1(x1, y1) and C2(x2, y2) and radius R1 and R2. Task is to check both circles A and B touch each other or not.
Examples :

```Input : C1 = (3,  4)
C2 = (14, 18)
R1 = 5, R2 = 8
Output : Circles do not touch each other.

Input : C1 = (2,  3)
C2 = (15, 28)
R1 = 12, R2 = 10
Output : Circles intersect with each other.

Input : C1 = (-10,  8)
C2 = (14, -24)
R1 = 30, R2 = 10
Input : -10 8
14 -24
30 10
Output : Circle touch each other.```

```Distance between centers C1 and C2 is calculated as
C1C2 = sqrt((x1 - x2)2 + (y1 - y2)2).
There are three condition arises.
1. If C1C2 == R1 + R2
Circle A and B are touch to each other.
2. If C1C2 > R1 + R2
Circle A and B are not touch to each other.
3. If C1C2 < R1 + R2
Circle intersects each other.```

## C++

 `// C++ program to check if two``// circles touch each other or not.``#include ``using` `namespace` `std;` `int` `circle(``int` `x1, ``int` `y1, ``int` `x2,``           ``int` `y2, ``int` `r1, ``int` `r2)``{``    ``int` `distSq = (x1 - x2) * (x1 - x2) +``                 ``(y1 - y2) * (y1 - y2);``    ``int` `radSumSq = (r1 + r2) * (r1 + r2);``    ``if` `(distSq == radSumSq)``        ``return` `1;``    ``else` `if` `(distSq > radSumSq)``        ``return` `-1;``    ``else``        ``return` `0;``}` `// Driver code``int` `main()``{``    ``int` `x1 = -10, y1 = 8;``    ``int` `x2 = 14, y2 = -24;``    ``int` `r1 = 30, r2 = 10;``    ``int` `t = circle(x1, y1, x2,``                   ``y2, r1, r2);``    ``if` `(t == 1)``        ``cout << ``"Circle touch to"``             ``<< ``" each other."``;``    ``else` `if` `(t < 0)``        ``cout << ``"Circle not touch"``             ``<< ``" to each other."``;``    ``else``        ``cout << ``"Circle intersect"``             ``<< ``" to each other."``;``    ``return` `0;``}`

## Java

 `// Java program to check if two``// circles touch each other or not.``import` `java.io.*;` `class` `GFG``{``    ``static` `int` `circle(``int` `x1, ``int` `y1, ``int` `x2,``                      ``int` `y2, ``int` `r1, ``int` `r2)``    ``{``        ``int` `distSq = (x1 - x2) * (x1 - x2) +``                     ``(y1 - y2) * (y1 - y2);``        ``int` `radSumSq = (r1 + r2) * (r1 + r2);``        ``if` `(distSq == radSumSq)``            ``return` `1``;``        ``else` `if` `(distSq > radSumSq)``            ``return` `-``1``;``        ``else``            ``return` `0``;``    ``}` `    ``// Driver code``    ``public` `static` `void` `main (String[] args)``    ``{``        ``int` `x1 = -``10``, y1 = ``8``;``        ``int` `x2 = ``14``, y2 = -``24``;``        ``int` `r1 = ``30``, r2 = ``10``;``        ``int` `t = circle(x1, y1, x2,``                       ``y2, r1, r2);``        ``if` `(t == ``1``)``            ``System.out.println ( ``"Circle touch to"` `+``                                 ``" each other."``);``        ``else` `if` `(t < ``0``)``            ``System.out.println ( ``"Circle not touch"` `+``                                 ``" to each other."``);``        ``else``            ``System.out.println ( ``"Circle intersect"` `+``                                 ``" to each other."``);``            ` `    ``}``}` `// This article is contributed by vt_m.`

## Python3

 `# Python3 program to``# check if two circles touch``# each other or not.` `def` `circle(x1, y1, x2, y2, r1, r2):`` ` `    ``distSq ``=` `(x1 ``-` `x2) ``*` `(x1 ``-` `x2) ``+` `(y1 ``-` `y2) ``*` `(y1 ``-` `y2);``    ``radSumSq ``=` `(r1 ``+` `r2) ``*` `(r1 ``+` `r2);``    ``if` `(distSq ``=``=` `radSumSq):``        ``return` `1``    ``elif` `(distSq > radSumSq):``        ``return` `-``1``    ``else``:``        ``return` `0`` `  `# Driver code``x1 ``=` `-``10``y1 ``=` `8``x2 ``=` `14``y2 ``=` `-``24``r1 ``=` `30``r2 ``=` `10` `t ``=` `circle(x1, y1, x2, y2, r1, r2)``if` `(t ``=``=` `1``):``    ``print``(``"Circle touch to each other."``)``elif` `(t < ``0``):``    ``print``(``"Circle not touch to each other."``)``else``:``    ``print``(``"Circle intersect to each other."``)` `# This code is contributed by``# Smitha Dinesh Semwal`

## C#

 `// C# program to check if two``// circles touch each other or not.``using` `System;` `class` `GFG``{``    ``static` `int` `circle(``int` `x1, ``int` `y1, ``int` `x2,``                      ``int` `y2, ``int` `r1, ``int` `r2)``    ``{``        ``int` `distSq = (x1 - x2) * (x1 - x2) +``                     ``(y1 - y2) * (y1 - y2);``        ``int` `radSumSq = (r1 + r2) * (r1 + r2);``        ``if` `(distSq == radSumSq)``            ``return` `1;``        ``else` `if` `(distSq > radSumSq)``            ``return` `-1;``        ``else``            ``return` `0;``    ``}` `    ``// Driver code``    ``public` `static` `void` `Main ()``    ``{``        ``int` `x1 = -10, y1 = 8;``        ``int` `x2 = 14, y2 = -24;``        ``int` `r1 = 30, r2 = 10;``        ``int` `t = circle(x1, y1, x2,``                       ``y2, r1, r2);``        ``if` `(t == 1)``            ``Console.WriteLine ( ``"Circle touch"` `+``                             ``" to each other."``);``        ``else` `if` `(t < 0)``            ``Console.WriteLine( ``"Circle not touch"` `+``                                ``" to each other."``);``        ``else``            ``Console.WriteLine ( ``"Circle intersect"` `+``                                 ``" to each other."``);``            ` `    ``}``}` `// This code is contributed by vt_m.`

## PHP

 ` ``\$radSumSq``)``        ``return` `-1;``    ``else``        ``return` `0;``}` `// Driver code``\$x1` `= -10; ``\$y1` `= 8;``\$x2` `= 14; ``\$y2` `= -24;``\$r1` `= 30; ``\$r2` `= 10;``\$t` `= circle(``\$x1``, ``\$y1``, ``\$x2``,``            ``\$y2``, ``\$r1``, ``\$r2``);``if` `(``\$t` `== 1)``    ``echo` `"Circle touch to each other."``;``else` `if` `(``\$t` `< 0)``    ``echo` `"Circle not touch to each other."``;``else``    ``echo` `"Circle intersect to each other."``;` `// This code is contributed by vt_m.``?>`

## Javascript

 ``

Output :

`Circle touch to each other.`

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