Differential decoding

 #include<stdio.h>  
 #include<conio.h>  
 int main()  
 {  
   int n,i,ascii[20],num,character[20],regester=0,reducedbit=0,requiredbit=0;  
   printf("enter the length\n");  
   scanf("%d",&n);  
   printf("enter %d numbers (first number should >65)\n",n);  
   for(i=0;i<n;i++)  
   {  
   scanf("%d",&ascii[i]);  
   num=ascii[i];  
       if(num<=127 && num>63)  
       reducedbit=reducedbit+7;  
       else if(num<=63 && num>31)  
       reducedbit=reducedbit+6;  
        else if(num<=31 && num>15)  
       reducedbit=reducedbit+5;  
        else if(num<=15 && num>7)  
       reducedbit=reducedbit+4;  
        else if(num<=7 && num>3)  
       reducedbit=reducedbit+3;  
        else if(num<=3 && num>1)  
       reducedbit=reducedbit+2;  
       else  
       reducedbit++;  
   }  
   printf("\n before decryption required bit is : %d\n\n",reducedbit);  
   printf("\n the decrypted text is :\n\n");  
   for(i=0;i<n;i++)  
   {  
   character[i]=ascii[i]+regester;  
   regester=character[i];  
   printf("%c",character[i]);  
   }  
   requiredbit=7*n;  
   printf("\n\n after decryption the required bit is : %d",requiredbit);  
   getch();  
 }