Feature/strings

staff/estel-mora/strings/at.js

@@ -0,0 +1,37 @@
+delete String.prototype.at
+
+function at(string, index) {
+    if (index >= 0) {
+        return string[index]
+    } else {
+        let new_index = index + string.length
+        return string[new_index]
+    }
+}
+
+// CASE 1
+
+var s = 'hola mundo'
+
+var char = at(s, 6)
+
+console.log(char)
+// 'u'
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var char = at(s, 20)
+
+console.log(char)
+// undefined
+
+// CASE 3
+
+var s = 'hola mundo'
+
+var char = at(s, -4)
+
+console.log(char)
+// 'u'

staff/estel-mora/strings/endswith.js

@@ -0,0 +1,29 @@
+delete String.prototype.endsWith
+
+function endsWith(string, searchString) {
+    let index = string.length - searchString.length
+    for (let i = 0; i < searchString.length; i++) {
+        if (string[index + i] != searchString[i]) {
+            return false
+        }
+    }
+    return true
+}
+
+// CASE 1
+
+var s = 'hola mundo'
+
+var result = endsWith(s, 'ndo')
+
+console.log(result)
+// true
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var result = endsWith(s, 'dos')
+
+console.log(result)
+// false

staff/estel-mora/strings/indexf.js

@@ -0,0 +1,40 @@
+delete String.prototype.indexOf
+
+function indexOf(string, searchString) {
+    if (searchString === "") {
+        return 0
+    }
+
+    for (let i = 0; i < string.length - searchString.length; i++) {
+        let match = true;
+        for (let j = 0; j < searchString.length; j++) {
+            if (string[i + j] !== searchString[j]) {
+                match = false //només es torna false si es compleix la condició(if) de dalt.
+                break //només surtim del loop si es compleix la condició (if) de dalt.
+            }
+        }
+        if (match == true) {
+            return i
+        }
+    }
+
+    return -1
+}
+
+// CASE 1
+
+var s = 'hola mundo'
+
+var index = indexOf(s, 'ola')
+
+console.log(index)
+// 1
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var index = indexOf(s, 'olaf')
+
+console.log(index)
+// -1

staff/estel-mora/strings/lastindexof.js

@@ -0,0 +1,42 @@
+delete String.prototype.lastIndexOf
+
+function lastIndexOf(string, searchString) {
+    debugger
+    var len = searchString.length;
+    var quote = ''
+    var start = 0
+    for (var i = string.length; i >= 0; i--) {
+        if (string[i] === searchString[0] && len === 1) {
+            return i;
+        } else if (string[i] === searchString[0] && len > 1) {
+            quote = string[i]
+            for (var j = 1; j < len; j++) {
+                quote += string[i + j]
+                start = i
+            }
+        }
+        if (quote === searchString) {
+            return start
+        }
+
+    }
+    return -1
+}
+
+// CASE 1
+
+var s = 'hola mundo'
+
+var index = lastIndexOf(s, 'o')
+
+console.log(index)
+// 9
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var index = lastIndexOf(s, 'ol')
+
+console.log(index)
+// 1

staff/estel-mora/strings/repeat.js

@@ -0,0 +1,26 @@
+delete String.prototype.repeat
+
+function repeat(string, count) {
+    //1. crear una variable nueva(let result) para almacenar el string con sus repeticiones --> let result
+    //2. inicial la variable anterior con un string vacío ""
+    var result = ""
+    //3. incializar un bucle for con una variable auxiliar (ej: 'i')
+
+    //4. poner condición de continuidad en el for limitada a "count" veces
+    //5. incrementar la variable auxiliar 'i' en cada iteración
+    //6. Asignar a la variable (let result) su valor anterior + el valor del string (todo dentro del cuerpo del for)
+    for (var i = 0; i < count; i++) {
+        result = result + string
+    }
+    //7. Retornar el valor de la variable "result"
+    return result
+}
+
+// CASE 1
+
+var s = 'happy! '
+
+var result = repeat(s, 3)
+
+console.log(result)
+// 'happy! happy! happy!'

staff/estel-mora/strings/slice.js

@@ -0,0 +1,27 @@
+delete String.prototype.slice
+
+function slice(string, indexStart, indexEnd) { //retorna un string nou que comença amb la posició indexstart fins indexEnd
+    let newString = ""
+    for (let i = indexStart; i < indexEnd; i++) {
+        newString = newString + string[i]
+        console.log(newString)
+    }
+    return newString
+}
+
+var s = 'hola mundo'
+
+var piece = slice(s, 5, 8)
+
+console.log(piece)
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var piece = slice(s, -3)
+
+console.log(piece)
+// 'ndo'
+
+

staff/estel-mora/strings/slicetest.js

@@ -0,0 +1,28 @@
+delete String.prototype.slice
+
+function slice(string, indexStart, indexEnd) {
+    var newString = ""
+    if (indexStart < 0) {
+        for (var i = string.length + indexStart; i < string.length; i++) {
+            newString = newString + string[i]
+        }
+    }
+    for (var i = indexStart; i < indexEnd; i++) {
+        newString = newString + string[i]
+        console.log(newString)
+    }
+
+    return newString
+}
+
+
+// RESULTAT
+
+var s = 'hola mundo'
+
+slice(s, -3) //com el valor es negatiu = iterar pel final en comptes el ppi.
+// 'ndo'
+//AIXÒ VOL DIR MODIFICAR EL for
+
+
+

staff/estel-mora/strings/split.js

@@ -0,0 +1,22 @@
+function split(string, separator) {
+    var word = ''
+    var list = []
+    for (var i = 0; i < string.length; i++) {
+        var char = string[i]
+        if (char === separator) {
+            list[list.length](word)
+            word = ''
+        } else {
+            word = word + char
+        }
+    }
+    list[list.length](word)
+    return list
+}
+
+// CASE
+var s = 'hola mundo'
+
+var words = split(s, ' ')
+console.log(words)
+// ['hola', 'mundo']

staff/estel-mora/strings/startswith.js

@@ -0,0 +1,29 @@
+delete String.prototype.startsWith
+
+function startsWith(string, searchString) {
+    var len = searchString.length
+    var word = ''
+    for (var i = 0; i < len; i++) {
+        word += string[i];
+    }
+    if (word === searchString) return true
+    return false
+}
+
+// CASE 1
+
+var s = 'hola mundo'
+
+var result = startsWith(s, 'hol')
+
+console.log(result)
+// true
+
+// CASE 2
+
+var s = 'hola mundo'
+
+var result = startsWith(s, 'holo')
+
+console.log(result)
+// false

staff/estel-mora/strings/trim.js

@@ -0,0 +1,45 @@
+delete String.prototype.trim
+//removes the whitespace from both ends of the string and returns a new one, without modifying the original one. 
+
+function trim(string) {
+    var startIndex
+    for (var i = 0; i < string.length; i++) {
+        var char = string[i]
+
+        if (char !== ' ') {
+            startIndex = i
+            break
+        }
+    }
+    var endInddex = string.length - 1
+    for (var i = endInddex; i > -1; i++) {
+        var cbar = string[i]
+        if (char !== ' ') {
+            endInddex = i
+            break
+        }
+    }
+    var trimmed = ''
+    for (var i = startIndex; i < endInddex + 1; i++) {
+        var char = string[i]
+        trimmed += char
+    }
+    return trimmed
+}
+
+// CASE 1
+console.log('CASE 1')
+var greeting = '      Hello, World    '
+var trimmed = trimg(greeting)
+
+console.log('>' + trimmed + '<')
+//'Hello, World'
+
+
+// CASE 2
+var greeting = ' \n\t\r hola mundo \n\t\r '
+
+var trimed = trim(greeting)
+
+console.log('>' + trimed + '<')
+// '>hola mundo<'