{"id":91533,"date":"2022-10-11T22:58:35","date_gmt":"2022-10-12T03:58:35","guid":{"rendered":"https:\/\/blogging-techies.com\/sw\/hur-man-hittar-summan-av-naturliga-tal-med-hjalp-av-rekursion\/"},"modified":"2022-10-11T22:58:35","modified_gmt":"2022-10-12T03:58:35","slug":"hur-man-hittar-summan-av-naturliga-tal-med-hjalp-av-rekursion","status":"publish","type":"post","link":"https:\/\/blogging-techies.com\/sw\/hur-man-hittar-summan-av-naturliga-tal-med-hjalp-av-rekursion\/","title":{"rendered":"Hur man hittar summan av naturliga tal med hj\u00e4lp av rekursion"},"content":{"rendered":"
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Rekursion \u00e4r en process d\u00e4r en funktion anropar sig sj\u00e4lv direkt eller indirekt. Rekursiva algoritmer anv\u00e4nds ofta inom datavetenskap f\u00f6r att l\u00f6sa komplexa problem genom att dela upp dem i enklare.<\/p>\n

Du kan b\u00e4ttre f\u00f6rst\u00e5 rekursiva begrepp genom att l\u00f6sa grundl\u00e4ggande programmeringsproblem som \u201cprodukten av tv\u00e5 tal\u201d, \u201csumman av f\u00f6rsta n naturliga talen\u201d och mer.<\/p>\n

I den h\u00e4r artikeln f\u00e5r du l\u00e4ra dig hur du hittar summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion.<\/p>\n

<\/span> Problembeskrivning<\/span><\/h2>\n

Du f\u00e5r ett naturligt tal n<\/strong>, m\u00e5ste du hitta summan av den f\u00f6rsta n<\/strong> naturliga tal med hj\u00e4lp av rekursion.<\/p>\n

Exempel 1<\/strong>: L\u00e5t n = 5<\/p>\n

D\u00e4rf\u00f6r \u00e4r summan av de f\u00f6rsta 5 naturliga talen = 1 + 2 + 3 + 4 + 5 = 15.<\/p>\n

Utg\u00e5ngen \u00e4r allts\u00e5 15.<\/p>\n

Exempel 2<\/strong>: L\u00e5t n = 7<\/p>\n

D\u00e4rf\u00f6r \u00e4r summan av de f\u00f6rsta 7 naturliga talen = 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28.<\/p>\n

Utg\u00e5ngen \u00e4r allts\u00e5 28.<\/p>\n

Exempel 3<\/strong>: L\u00e5t n = 6<\/p>\n

D\u00e4rf\u00f6r \u00e4r summan av de f\u00f6rsta 6 naturliga talen = 1 + 2 + 3 + 4 + 5 + 6 = 21.<\/p>\n

Utg\u00e5ngen \u00e4r allts\u00e5 21.<\/p>\n

<\/span> Rekursiv funktion f\u00f6r att hitta summan av de f\u00f6rsta N naturliga talen<\/span><\/h2>\n

De flesta rekursiva funktioner har f\u00f6ljande relativa struktur:<\/p>\n

FUNCTION nameIF condition THENRETURN resultELSECALL FUNCTION nameEND FUNCTION<\/pre>\n
F\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen, observera och till\u00e4mpa f\u00f6ljande pseudokod:<\/p>\n
findSum(n):IF n<=1 THENRETURN nELSERETURN n + findSum(n-1)END FUNCTION<\/pre>\n
Nu kan du implementera denna pseudokod p\u00e5 ditt favoritspr\u00e5k.<\/p>\n
Notera<\/strong>: Du kan ocks\u00e5 hitta summan av de f\u00f6rsta n naturliga talen med f\u00f6ljande matematiska formel:<\/p>\n
Summan av n naturliga tal = n * (n + 1) \/ 2<\/p>\n
Med denna metod kan du hitta summan i ett steg utan att anv\u00e4nda rekursion.<\/p>\n
<\/span>  C++-implementering f\u00f6r att hitta summan av f\u00f6rsta N naturliga tal med hj\u00e4lp av rekursion<\/span><\/h2>\n
Nedan \u00e4r C++-implementationen f\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion:<\/p>\n
\/\/ C++ implementation to find the sum of\/\/ first n natural numbers using recursion#include <iostream>using namespace std;\/\/ Recursive function to find the sum of first n natural numbersint findSum(int n){if (n<=1){return n;}else{return n + findSum(n-1);}}\/\/ Driver codeint main(){int n1 = 5, n2 = 7, n3 = 6;cout << \"n1: \" << n1 << endl;cout << \"n2: \" << n2 << endl;cout << \"n3: \" << n3 << endl;cout << \"Sum of first \" << n1 << \" natural numbers: \" << findSum(n1) << endl;cout << \"Sum of first \" << n2 << \" natural numbers: \" << findSum(n2) << endl;cout << \"Sum of first \" << n3 << \" natural numbers: \" << findSum(n3) << endl;return 0;}<\/pre>\n
Produktion:<\/p>\n
n1: 5 n2: 7 n3: 6 Sum of first 5 natural numbers: 15 Sum of first 7 natural numbers: 28 Sum of first 6 natural numbers: 21<\/pre>\n
<\/span>  Python-implementering f\u00f6r att hitta summan av de f\u00f6rsta N naturliga talen med hj\u00e4lp av rekursion<\/span><\/h2>\n
Nedan \u00e4r Python-implementationen f\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion:<\/p>\n
# Python implementation to find the sum of# first n natural numbers using recursion# Recursive function to find the sum of first n natural numbersdef findSum(n):if n<=1:return nelse:return n + findSum(n-1)# Driver Coden1 = 5n2 = 7n3 = 6print(\"n1: \", n1)print(\"n2: \", n2)print(\"n3: \", n3)print(\"Sum of first \", n1, \" natural numbers: \", findSum(n1))print(\"Sum of first \", n2, \" natural numbers: \", findSum(n2))print(\"Sum of first \", n3, \" natural numbers: \", findSum(n3))<\/pre>\n
Produktion:<\/p>\n
n1: 5 n2: 7 n3: 6 Sum of first 5 natural numbers: 15 Sum of first 7 natural numbers: 28 Sum of first 6 natural numbers: 21<\/pre>\n
<\/span>  C Implementering f\u00f6r att hitta summan av f\u00f6rsta N naturliga tal med hj\u00e4lp av rekursion<\/span><\/h2>\n
Nedan \u00e4r C-implementationen f\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion:<\/p>\n
\/\/ C implementation to find the sum of\/\/ first n natural numbers using recursion#include <stdio.h>\/\/ Recursive function to find the sum of first n natural numbersint findSum(int n){if (n<=1){return n;}else{return n + findSum(n-1);}}\/\/ Driver codeint main(){int n1 = 5, n2 = 7, n3 = 6;printf(\"n1: %d \u2060n\", n1);printf(\"n2: %d \u2060n\", n2);printf(\"n3: %d \u2060n\", n3);printf(\"Sum of first %d natural numbers: %d \u2060n\", n1, findSum(n1));printf(\"Sum of first %d natural numbers: %d \u2060n\", n2, findSum(n2));printf(\"Sum of first %d natural numbers: %d \u2060n\", n3, findSum(n3));return 0;}<\/pre>\n
Produktion:<\/p>\n
n1: 5 n2: 7 n3: 6 Sum of first 5 natural numbers: 15 Sum of first 7 natural numbers: 28 Sum of first 6 natural numbers: 21<\/pre>\n
<\/span>  JavaScript-implementering f\u00f6r att hitta summan av de f\u00f6rsta N naturliga talen med hj\u00e4lp av rekursion<\/span><\/h2>\n
Nedan \u00e4r JavaScript-implementeringen f\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion:<\/p>\n
\/\/ JavaScript implementation to find the sum of\/\/ first n natural numbers using recursion\/\/ Recursive function to find the sum of first n natural numbersfunction findSum(n) {if (n<=1) {return n;} else {return n + findSum(n-1);}}
\/\/ Driver Codevar n1 = 5, n2 = 7, n3 = 6;document.write(\"n1: \" + n1 + \"<br>\");document.write(\"n2: \" + n2 + \"<br>\");document.write(\"n3: \" + n3 + \"<br>\");document.write(\"Sum of first \" + n1 + \" natural numbers: \" + findSum(n1) + \"<br>\");document.write(\"Sum of first \" + n2 + \" natural numbers: \" + findSum(n2) + \"<br>\");document.write(\"Sum of first \" + n3 + \" natural numbers: \" + findSum(n3) + \"<br>\");<\/p><\/pre>\n
Produktion:<\/p>\n
n1: 5 n2: 7 n3: 6 Sum of first 5 natural numbers: 15 Sum of first 7 natural numbers: 28 Sum of first 6 natural numbers: 21<\/pre>\n
<\/span>  Java-implementering f\u00f6r att hitta summan av f\u00f6rsta N naturliga tal med hj\u00e4lp av rekursion<\/span><\/h2>\n
Nedan \u00e4r Java-implementeringen f\u00f6r att hitta summan av de f\u00f6rsta n naturliga talen med hj\u00e4lp av rekursion:<\/p>\n
\/\/ Java implementation to find the sum of\/\/ first n natural numbers using recursionpublic class Main{\/\/ Recursive function to find the sum of first n natural numberspublic static int findSum(int n){if (n <= 1){return n;}else{return n + findSum(n - 1);}}\/\/ Driver codepublic static void main(String[] args){int n1 = 5, n2 = 7, n3 = 6;System.out.println(\"n1: \" + n1);System.out.println(\"n2: \" + n2);System.out.println(\"n3: \" + n3);System.out.println(\"Sum of first \" + n1 + \" natural numbers: \" + findSum(n1));System.out.println(\"Sum of first \" + n2 + \" natural numbers: \" + findSum(n2));System.out.println(\"Sum of first \" + n3 + \" natural numbers: \" + findSum(n3));}}<\/pre>\n
Produktion:<\/p>\n
n1: 5 n2: 7 n3: 6 Sum of first 5 natural numbers: 15 Sum of first 7 natural numbers: 28 Sum of first 6 natural numbers: 21<\/pre>\n
<\/span>  L\u00e4r dig mer om rekursion<\/span><\/h2>\n
Rekursivt t\u00e4nkande \u00e4r mycket viktigt i programmering.  Ibland kan den rekursiva l\u00f6sningen vara enklare att l\u00e4sa \u00e4n den iterativa.  Du kan l\u00f6sa m\u00e5nga problem som Tower of Hanoi Problem, DFS of Graph, Inorder\/Preorder\/Postorder Tree Traversals, etc., med hj\u00e4lp av rekursion.<\/p>\n
Rekursion \u00e4r en mycket kraftfull probleml\u00f6sningsstrategi.  Numera anv\u00e4nds det ocks\u00e5 flitigt i funktionell programmering.  Du m\u00e5ste k\u00e4nna till grunderna f\u00f6r rekursion och hur du kan till\u00e4mpa den i dina programmeringsstr\u00e4vanden.<\/p>\n
    Om f\u00f6rfattaren<\/strong><\/p>\n
            Yuvraj Chandra (80 artiklar publicerade)
<\/strong><\/p>\n
Yuvraj \u00e4r en datavetenskapsstudent vid University of Delhi, Indien.  Han brinner f\u00f6r Full Stack Web Development.  N\u00e4r han inte skriver unders\u00f6ker han djupet i olika teknologier.<\/p>\n
                            Mer fr\u00e5n Yuvraj Chandra<\/p>\n
<\/span>Prenumerera p\u00e5 v\u00e5rt nyhetsbrev<\/span><\/h4>\n
G\u00e5 med i v\u00e5rt nyhetsbrev f\u00f6r tekniska tips, recensioner, free e-b\u00f6cker och exklusiva erbjudanden!<\/p>\n
Klicka h\u00e4r f\u00f6r att prenumerera<\/p>\n<\/p><\/div>\n  
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