reverse

I am currently studying C and I can't get past this exercise. I must create a recursive function to reverse string1 into string2 . Here is my code. I would gladly appreciate your help. #include <stdio.h> #define MAX 100 void reverse(char s1[],char s2[],int n,int j); int main() { char string1[MAX]="How Are You Mate"; char string2[MAX]=""; int n=0; int i=0; int j=0; for(i=0;string1[i]!='\0';i++) n++; reverse(string1,string2,n,j); printf("String-a normal:\n%s\n",string1); printf("String-a reverse:\n%s\n",string2); return 0; } void reverse(char s1[],char s2[],int n,int j) { if(n>0) { s2[j]=s1[n];

I'm in need of a little help reversing a section of a list in Python using a loop. I have a list: mylist = ['a', 'b', 'c', 'd', 'e', 'f'] Also have an index number, this number will tell where to start the reversing. For example, if the reverse-index number is 3, it needs to be something like this: ['d', 'c', 'b', 'a', 'e', 'f'] What I currently have: def list_section_reverse(list1, reverse_index): print("In function reverse()") n_list = [] for item in range( len(list1) ): n_list.append( (list1[(reverse_index - 1) - item]) ) item += 1 return n_list mylist = ['a', 'b', 'c', 'd', 'e', 'f'] print

This question already has an answer here: JavaScript: How to reverse a number? 8 answers Can anyone show me where I'm going wrong in my code please? I'm trying to reverse a number without changing it to a string. I've been searching google and looked through the previous questions asked about this topic and from what I can see my code mirrors the other answers. I've only been able to find code in Java, C, or C++ that do not use the to string method. In my attempts, when I run the code in the browser console it either gives me an answer of "Infinity" or crashes my browser. Here's my code...

I want to reverse a string each two characters with Ruby. The input: "0123456789abcdef" The output that I expect: "efcdab8967452301" I'm not sure if this is the best way to do it: "0123456789abcdef".scan(/../).reverse.join == "efcdab8967452301" "0123456789abcdef".gsub(/../, &:reverse).reverse # => "efcdab8967452301" You can try: "0123456789abcdef".chars.each_slice(2).to_a.reverse.join I like all the solutions, especially @sawa's, but now, six hours later, its a challenge to come up with something different. In the interest of diversity, I offer a way that uses pairwise substitution. It's

I'm trying to sort a list and I can't figure out to reverse the order of a second sorting characteristic. import math ps = {1:(1,1),2:(3,2),3:(3,-3),4:(-3,4),5:(-2,-2),6:(3,3),7:(1,-1)} l = [] for x in range(1,8): l.append((math.atan2(ps[x][1],ps[x][0]),ps[x])) for c in sorted(l, key = lambda t:(t[0], math.sqrt((0-t[1][0])**2 + (0-t[1][1])**2)),reverse = True): print(c) The first sort characteristic is sorting by angle, the second sorts by distance from the origin if the angle is equal. Does anyone know how to do this. Thanks in advance for the help. Put a minus sign in front of the second