Thread: Copying variable to array or splitting input

okay im having some problems taking a whole number from input say 1234 and spliting it up in to individuality numbers and then storing them in a variable. For example i though i could do something like this

Code:

int numberinputbyuser;
int numberarray [5];

scanf("%d"numberinputbyuser);
 strcpy(numberarray ,numberinputbyuser);

and maby that will alow me to refrence each part of the numbers inputed from say array space 0 would be 1 and number 1 would be 2 so on but i dont think it works like that. either way some help would be great

After you have the number to split up you're supposed to use math to get the digits and assign them into an array.

you computers memory doesn't work like that. computers do not understand base 10 number systems. they only understand binary, a base 2 number system. when you declare an int data type and send a number to it the numbers are not stored in individual sequential blocks.

for instance, if you declared;

int x[10];

your telling the computer too set aside 10 blocks of memory with the size of int data type.

when you declare;

int y;

your telling the computer to set aside 1 block in memory with a size of 1 int data type.

when you send an int data type like 123456 too x[];

x[0]= 123456

all of that data is stored in the first element of x[]; which is x[0],
none of the other blocks of data are altered (x[1] --> x[9]).

instead of thinking of the numbers as numbers you could treat them as characters. for instance;

char x[10] = "123456789";
char y;
y= x[3];

in this way y is now equal too '4', that is the character 4, not the number 4. the draw back of this is that you can't easily do math using the data array x[0] because when you use it as an operand your CPU runs the calculation using the byte code of '4' which is not equal to the number 4.

Since the input is an integer, you can use the itoa() function to convert into a string and to store it into an integer array, by using a loop you can use string[i]-'0' to get the individual integer digits. Store them in an int array( in the same loop).

Originally Posted by BeNNs

okay im having some problems taking a whole number from input say 1234 and spliting it up in to individuality numbers and then storing them in a variable. For example i though i could do something like this

Code:

int numberinputbyuser;
int numberarray [5];

scanf("%d"numberinputbyuser);
 strcpy(numberarray ,numberinputbyuser);

and maby that will alow me to refrence each part of the numbers inputed from say array space 0 would be 1 and number 1 would be 2 so on but i dont think it works like that. either way some help would be great

Code:

char x[10];
int y;

scanf(" %9s", x);

printf("The digits are...");
for (y = 0; y < strlen(x); y++)
  { x[y] -= '0';
   printf("  %d", x[y]); }

printf("\n\nthe third digit is %d", x[3]);

If you know they are all single digit numbers, you can convert them from ascii and use them as actual numbers in your program.