JavaScript | Reverse a string in place.
In order to reverse the string in its place, We’re going to use a number of methods and the most preferred ones.
We’re going to use these methods(click to know more).
Example-1: This example reverses the string by first splitting it with (“”) separator and then reversing it and finally joining it by (“”) separator.
<!DOCTYPE html> < html > < head > < title > JavaScript | Reverse a string in place. </ title > </ head > < body style = "text-align:center;" id = "body" > < h1 style = "color:green;" > GeeksForGeeks </ h1 > < p id = "GFG_UP" style = "font-size: 16px; font-weight: bold;" > </ p > < button onclick = "gfg_Run()" > Inplace Reverse </ button > < p id = "GFG_DOWN" style="color:green; font-size: 20px; font-weight: bold;"> </ p > < script > var el_up = document.getElementById("GFG_UP"); var el_down = document.getElementById("GFG_DOWN"); var str = 'This is GeeksForGeeks'; el_up.innerHTML = "String = " + "'" + str + "'"; function gfg_Run() { el_down.innerHTML = str.split("").reverse().join(""); } </ script > </ body > </ html > |
Output:
- Before clicking on the button:
- After clicking on the button:
Example-2: This example uses the concept of merge sort algorithm.
<!DOCTYPE html> < html > < head > < title > JavaScript | Reverse a string in place. </ title > </ head > < body style = "text-align:center;" id = "body" > < h1 style = "color:green;" > GeeksForGeeks </ h1 > < p id = "GFG_UP" style="font-size: 16px; font-weight: bold;"> </ p > < button onclick = "gfg_Run()" > Inplace Reverse </ button > < p id = "GFG_DOWN" style="color:green; font-size: 20px; font-weight: bold;"> </ p > < script > var el_up = document.getElementById("GFG_UP"); var el_down = document.getElementById("GFG_DOWN"); var str = 'This is GeeksForGeeks'; el_up.innerHTML = "String = " + "'" + str + "'"; function reverse(s) { if (s.length < 2 ) return s; var hIndex = Math .ceil(s.length / 2); return reverse(s.substr(hIndex)) + reverse(s.substr(0, hIndex)); } function gfg_Run() { el_down.innerHTML = reverse (str); } </script> </ body > </ html > |
Output:
- Before clicking on the button:
- After clicking on the button:
Example-3:This example takes a variable and appending the result from the end of the string.
<!DOCTYPE html> < html > < head > < title > JavaScript | Reverse a string in place. </ title > </ head > < body style = "text-align:center;" id = "body" > < h1 style = "color:green;" > GeeksForGeeks </ h1 > < p id = "GFG_UP" style="font-size: 16px; font-weight: bold;"> </ p > < button onclick = "gfg_Run()" > Inplace Reverse </ button > < p id = "GFG_DOWN" style="color:green; font-size: 20px; font-weight: bold;"> </ p > < script > var el_up = document.getElementById("GFG_UP"); var el_down = document.getElementById("GFG_DOWN"); var str = 'A Computer Science Portal' el_up.innerHTML = "String = " + "'" + str + "'"; function reverse(s { for(var i = s.length - 1, o = ''; i >= 0; o += s[i--]) {} return o; } function gfg_Run() { el_down.innerHTML = reverse(str); } </ script > </ body > </ html > |
Output:
- Before clicking on the button:
- After clicking on the button: