separate numbers and string into text and numbers - c

Question

I am trying to write code where I can separate string and numbers.
The string I have to separate it completely already the numbers I have to separate every 2 numbers.
My Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
void getString(const char *str) {
char nums[50];
char alphas[50];
for (int i = 0; i < strlen(str); i++) {
if (isdigit(str[i]))
strcpy(nums, str);
if (isalpha(str[i]))
strcpy(alphas, str);
}
printf("str: %s\n", alphas);
printf("num: %d\n", atoi(nums));
}
int main() {
char *str = "one01two02three03";
getString(str);
return 0;
}
What I'm trying to do should return me as follows
str: onetwothree
num1: 01
num2: 02
num3: 03

Answer 1

The following parses the input and produces the correct output.
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
int *nums = NULL;
int num_count = 0;
char save_num(int n)
{
nums = realloc(nums, sizeof(int)*(num_count+1));
nums[num_count++] = n;
return '\0';
}
void getString(const char *str)
{
char* alpha = malloc(strlen(str)+1);
char* num = malloc(strlen(str)+1);
size_t i;
alpha[0] = '\0';
num[0] = '\0';
for (i = 0; i < strlen(str); i++)
{
if (isdigit(str[i]))
strncat(num, str+i, 1);
else if(isalpha(str[i]))
{
strncat(alpha, str+i, 1);
if(strlen(num) > 0)
num[0] = save_num(atoi(num));
}
}
if(strlen(num) > 0)
save_num(atoi(num));
printf("str: %s\n", alpha);
for(i = 0 ; i < num_count ; ++i)
printf("num%Zu: %02d\n", i+1, nums[i]);
free(alpha);
free(num);
}
int main()
{
char *str = "one01two02three03";
getString(str);
return 0;
}

Answer 2

This provides what you have asked for:
void getString(const char *str)
{
char one[10],two[10],three[10];
int x,y,z;
char a[10],b[10],c[10];
sscanf(str,"%[^0-9]""%[0-9]""%[^0-9]""%[0-9]""%[^0-9]""%[0-9]",a,one,b,two,c,three);
x = atoi(one);
y = atoi(two);
z = atoi(three);
printf("str: %s%s%s\n",a,b,c);
printf("num: %d\n",x);
printf("num: %d\n",y);
printf("num: %d\n",z);
}
Don´t forget to provide the declaration of getString before main():
void getString(const char *str);
So all together:
#include <stdio.h>
void getString(const char *str);
int main()
{
char *str = "one01two02three03";
getString(str);
return 0;
}
void getString(const char *str)
{
char one[10],two[10],three[10];
int x,y,z;
char a[10],b[10],c[10];
sscanf(str,"%[^0-9]""%[0-9]""%[^0-9]""%[0-9]""%[^0-9]""%[0-9]",a,one,b,two,c,three);
x = atoi(one);
y = atoi(two);
z = atoi(three);
printf("str: %s%s%s\n",a,b,c);
printf("num: %d\n",x);
printf("num: %d\n",y);
printf("num: %d\n",z);
}
Output:
str: onetwothree
num: 01
num: 02
num: 03

Answer 3

Since you have already set your strings 'nums' and 'alphas' there is no need to handle them dynamically.You should just copy the elements of the array str,one by one, to either the array num or the array alphas.
To distinguish different numbers just put a special character between numbers in the num array.
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
void getString(const char *str)
{
char nums[50];
char alphas[50];
int digits = 0;
int alpha = 0;
for (int i = 0; i < strlen(str); i++) {
if (isdigit(str[i])){
while(isdigit(str[i])){
nums[digits] = str[i];
i++;
digits++;
}
nums[digits]='\n';
digits++;
}
if(isalpha(str[i])){
alphas[alpha] = str[i];
alpha++;
}
}
printf("str: %s\n", alphas);
int n,p=0;
char subbuf[5];
for(n=0;n<digits;n++){
p=n;
while(nums[n]!='\n'){
n++;
}
memcpy(subbuf,&nums[p],n-p);
printf("num: %d\n", atoi(subbuf));
}
}
int main()
{
char *str = "01two02three03";
getString(str);
return 0;
}
Be aware that strcpy sets the pointer of the first argument to point to the second argument,this means that when you write strcpy(nums,str) in your code above, you copy the entire str string to the num several times.

Answer 4

Using an array for this question is not necessary, unless the array is to be used later. So my answer to this question is short and simple:
#include <stdio.h>
#include <stdbool.h>
void getString(const char *str)
{
bool in_number = false;
while (*str) {
if (*str >= '0' && *str <= '9') {
if (!in_number) { // Transition from a non-digit to digit
printf(": ");
in_number = true;
}
} else if (in_number) { // Transition from a digit to non-digit
putchar('\n');
in_number = false;
}
putchar(*str++);
}
putchar('\n');
}
int main(void)
{
char *str = "one01two02three03";
getString(str);
return 0;
}
The boolean variable in_number is used to catch the transitions from a digit character to a non-digit character and from a non-digit character to a digit character.