Thread: [Help] About reverse string

I must Write a program using getchar() function only to read the character string from the keyboard until ‘.’ is terminated, then reverse the string and display result on on the screen.

I don't know why but my program doesn't run right. Can anyone help me, pls. And this is my code:

Code:

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#include<string.h>

main()
{
   unsigned int choice, i, j, n;
   char c, temp;
   char s1[100], s2[100];
   while(1){
   do{
       system("cls");
       printf("Choose one of the following options: ");
       printf("\n1. Input a string");
       printf("\n2. Dislay a string");
       printf("\n3. Reverse a string");
       printf("\n0. Exit");
       printf("\nYour selection (0 -> 3): ");
       scanf("%d", &choice);}
   while(choice<0 || choice>3);
   switch(choice){
                     case 1: printf("\nEnter string ended by . : ");
                             for(i=0; (c=getchar()) != '.'; i++) s1[i]=c;
                             n=strlen(s1);
                             for(i=0;i<n;i++)
                                if (s1[i]=='\n') 
                                    {
                                       for(j=i;j<n;j++) s1[j]=s1[j+1];
                                       s1[n--]='\0';
                                       i--;
                                    }
                             strcpy(s2,s1);
                             system("pause");
                             break;
                     case 2: printf("String entered is \" ");
                             for(i=0;i<n;i++) printf("%c", s1[i]);
                             printf(" \" \n");
                             system("pause");
                             break;
                     case 3: for(i=0;i<n-1;i++)
                                for(j=i+1;j<n;j++)
                                {
                                   temp=s2[i];
                                   s2[i]=s2[j];
                                   s2[j]=temp;
                                };
                             printf("The orginal string: ");
                             for(i=0;i<n;i++) printf("%c", s1[i]);
                             printf("\n");
                             printf("The reverse string: ");
                             for(i=0;i<n;i++) printf("%c", s2[i]);
                             printf("\n");
                             system("pause");
                             break;
                     case 0: exit(0);}}
}

I have fixed my program.
It should have "fflush(stdin)" in case 1