Thread: any solution to convert given char*(number) to required unsigned char*(hex of number)

Given For e.g,

Code:

char input[] = "10011210582553796";

now Hexadecimal of 10011210582553796 is 2391249A8B74C4.

So output unsigned char* should have value,

Code:

unsigned char output[8] = {0x00,0x23,0x91,0x24,0x9A,0x8B,0x74,0xC4};

Any solution to convert given input char* to output char* with above mentioned requirement.

code should run on platform for which __int64/signed long long is not supported.

Thanx in advance...

Hi zacs7,

The number i have given is out of range of int datatype, so can not use printf of or atoi operation which are supported for int datatype. Actually number can be stored in int64 type but system does not support int64 datatype. So i want to convert is to

Code:

unsigned char output[8] = {0,35,145,36,154,139,116,196}  = {0,0x23,0x91,0x24,0x9A,0x8B,0x74,0xC4}

Even i cannot use left shift or right shift (multiplication/devision) when number reaches above integer capacity.

found solution...

Code:

     int number = 0;
     char numberchars[] = "10011210582553796";
     int i = 0;
     int ans = 0;
     int carry = 0;

     char answerArray[100] = {0};

     char remainderArray[100] = {0};
     int remindex = 0;
     int ansindex = 0;
     int remainder = 0;

     while( numberchars[i] != '\0' )
     {
          while( numberchars[i] != '\0' )
          {
               char currentchar[2] = {0};
               currentchar[0]=numberchars[i];

               int num = atoi(currentchar);
               num += remainder;
               remainder = 0;

               if ( num < 2  )
               {               
                    remainder = num;
                    if(i>0)
                         answerArray[ansindex++] = '0';
               }
               else
               {
                    remainder = num % 2;
                    int answer = num / 2;

                    char a[2] = {0};
                    itoa(answer,a,10);

                    answerArray[ansindex++] = a[0];
               }

               i++;
               remainder *= 10;
          }

          char a[2] = {0};
          int rval = remainder / 10;
          itoa(remainder / 10,a,10);
          
          remainderArray[remindex++] = a[0];
          int size = sizeof(answerArray);
          memcpy(numberchars,answerArray,sizeof(answerArray));
           size = sizeof(answerArray);
          memset(answerArray,0,sizeof(answerArray));
          ansindex = 0;
          remainder = 0;
          i=0;
     }

     char int64[8] = {0};

     for(int k=0;remainderArray[k]!= '\0';k++)
     {
          int64[7-(k/8)] |= ((remainderArray[k]-'0') << (k%8));
     }

Have your tested that solution? itoa is not properly defined how have you declaried your 'a' string for the function call?