I have given a task to generate a sub string for the given input in C. The code as follows.
#include<stdio.h>
int main(){
char a[1000];
char *sub;
int startFrom = 0;
int endAt = 0;
printf("Enter the String: ");
scanf("%s", a);
printf("Start From? ");
scanf("%d", &startFrom);
printf("End At? ");
scanf("%d", &endAt);
sub = &a[startFrom];
a[endAt] = '\0';
printf("%s\n", sub);
return 0;
}
The code however works fine, but what will happen to the rest of the characters in the array?
The rest of the array remains the same; it's just that you changed one of the characters in the array to null('\0'). So if you try to access any other character after (or before) the a[endAt] character, you would be able to do so.
Check it out Your code with some extra at Ideone.com.
However as you can see, when you try to print the original array, it would be printed only till the first '\0' character.
Related
#include <stdio.h>
#include<string.h>
int main(void)
{
int n,u = 0;
printf("Enter length of word ");
scanf("%d",&n);
char word[n*2];
printf("Enter the String \n");
scanf("%s", word);
printf("string that u have entered: %s\n",word);
int i = n - 1, j = n;
while(i >= 0)
{
printf("word[i-1] %c\n",word[i]);
word[j] = word[i];
printf("i %d\n",i);
printf("j %d\n",j);
i--;
j++;
}
printf("reversed word stored at the last in the same array - %s\n",word);
}
when we give the length 3 the output doesn't give any garbage value in output but when I give greater than 3 its starts to give garbage value in the output. (yeah I know we have to add '\0' at the end of the array to stop but for length 3 without that, it works.)
Here, you have declared the word as char array and alloted the size of array. So,when you are printing via indexing of array as %c --it gives the correct result. But,at the end,when you try to print the whole 'word' char array, you used %s . Now, what %s does is : when you indicate to a string, it stores the address of the first element and keep printing the value stored in those addresses in sequential manner untill it finds the null value. So,you better use a loop to print values stored in 'word' array using %c or you can convert your char array 'word' into string & then use %s to print values inside 'word'.
I want to store "char data type values" in an array, but it doesn't work.
First, I tried using "gets"
but it gave me a run time error.
Code was like this
int tmp = 0;
char arr[100] = { 0, };
while (arr[tmp]!=NULL)
{
gets(arr[tmp]);
tmp++;
}
for (int rtmp = 0; rtmp < a; rtmp++)
printf("%s ", arr[rtmp]);
return 0;
In a second way, I was using "scanf", but I couldn't store "char data type(it should be more than one character like string)", but only one character was available.(I tried %s, but it doesn't work)
Plus, it doesn't print the last value of array.
int a = 0;
scanf("%d", &a); //determine how much I input values
int tmp = 0;
char arr[100] ={ 0 , };
for(tmp=0;tmp<a;tmp++)
{
scanf("%c ",arr[tmp]);
fflush(stdin);
}
for (int rtmp = 0; rtmp < a; rtmp++)
printf("%c ", arr[rtmp]);
return 0;
The most "identical" for me is
without notifying "a" values("a" means how much values I input)
and storing "char values" in array..
How can I solve this problem?
Thanks in advance! Your help is always appreciated :)
Array of char data type is called Sting. You can take a string's input using scanf() and gets(). But if you use scanf(), the string will be input by pressing Space-bar or Enter. But if you use gets(), input will be given only by pressing the Enter key.
Example 1:
char s[100];
scanf("%s", s);
Example 2:
char s[100];
gets(s);
Now, if you want to input every single character individually, you can do that also:
char s[100], c;
int n, i, j;
scanf("%d", &n);
getchar();
for(i=0; i<n; i++) {
scanf("%c", &s[i]);
}
s[i] = '\0';
Now look, I wrote a getchar() after scanf("%d", &n);, because when you press enter after inputting n, a new line character ('\n') is also taken as input in the character next to n. So you must do this in case like this.
One more thing, you can take input any string containing spaces using scanf() also. Just do this:
char s[100];
scanf("%[^\n]", s);
You can not enter the individual character by following snippet of code.
char arr[10] = {0};
//unsigned char ch;
unsigned int i = 0;
printf("Enter the array elements\n");
for(i = 0; i<10; i++)
{
scanf("%c", &arr[i]);
printf("i = %d and arr[%d] = %c\n", i, i, arr[i]);
}
The result of this snippet is as per this image. enter image description here
To avoid this issue, it is recommended to enter the character without new line charactoer '\n' or without pressing enter.
Or other method is to use the array as string and input the character by gets() like this snippet.
char s[100];
gets(s);
I'm new to C and have been set the following problem. I am to write a program where a string can be entered and stored, I should then enter two integer values which will then be used to remove characters from the string, afterwards the result should be printed. Once the program works it should be converted into a function.
I have created a program that will split the entered string into two strings which store the chars I want to keep in two buffers, afterwards the two strings are concatenated to give the resultant edited string. The problem I am having is that when I print the edited string I get random characters at the end and sometimes in between the two strings and I think it's because the strings are not being null terminated correctly. I hope that someone is able to help, Thanks :)
#include <stdio.h>
#include <string.h>
int main ()
{
char string [25];
char buffer1 [25];
char buffer2 [25];
int start;
int remove;
int i;
int finish;
int size;
int numbercopy;
int A, B, C;
printf("Enter a string: ");
gets(string);
printf("\nEnter a starting character position: ");
scanf("%d", &start);
printf("\nHow many characters would you like to remove? ");
scanf("%d", &remove);
finish = (start+remove);
size = strlen(string);
numbercopy = (size-finish);
strncpy(&buffer1[0], &string[0], start);
buffer1[start] = '\0';
strncpy(&buffer2[0], &string[finish], numbercopy);
buffer2[numbercopy] = '\0';
A = strlen(buffer1);
B = strlen(buffer2);
C = (A+B);
strcat(buffer1, buffer2);buffer1[C] = '\0';
for (i=0; i<25; i++)
{
printf("%c", buffer1[i]);
}
return 0;
}
Since it is a string, you do not need to print it character by character. Also, the loop indicates that only 25 char strings will be printed. If a string (buffer1) is shorter in length(<25), garbage values will be printed, if a string is is larger (>25), some chars will not be printed.
Change this:
for (i=0; i<25; i++)
{
printf("%c", buffer1[i]);
}
to this:
printf("%s", buffer1);
this is my first time using this site as well as learning c programming.
I'm trying to write a code which lets a user type in a sentence and the code prints it back out.
My attempt:
#include<stdio.h>
int main()
{
char array[1000];
printf("Please enter a phrase: ");
int index = 0;
while(array[index]!= '\0')
{
scanf("%c",&array[index]);
++index;
}
index = 0;
while(array[index]!= '\n')
{
printf("%c",array[index]);
++index;
}
}
I can't find the reason to why this code does not work.
You can get expected output using your concept also.. Try something using following code.
#include<stdio.h>
int main()
{
char array[1000];
printf("Please enter a phrase: ");
int index =0;
scanf("%c",&array[index]);
while(array[index]!='\n')
{
scanf("%c",&array[++index]);
}
index=0;
while(array[index]!= '\n')
{
printf("%c",array[index]);
++index;
}
printf("\n");
}
Okay, so first and foremost you'll need to initialize all your array. If you don't, the user input will print along with lots of meaningless garbage.
Secondly, the test portion of your first while loop checks for a null character which will never exist because "array[]" is just a simple character array (not a string) therefore, a call to scanf() doesn't insert the null character at the end. This causes an infinite loop.
Thirdly, your first while loop should be a do-while so that you first read a character, then test the character, otherwise if the "index" variable increments first...
Lastly, I posted the code that i used to get it to run using the method that you chose. However, as an alternative to the method you chose, the c standard library has the gets() function, which will allow you to read an entire line of input and return the string entered (actually it returns a pointer to the character array created but i think you catch my drift), and the puts() function which prints a string pointed to by the pointer used as an argument.
For more info on this problem in general, including gets() and puts(), refer to "C Programming A Modern Approach" by K.N. King, Chapter 13: Strings.I hope this helps.
Happy Coding!! :)
#include <stdio.h>
int main()
{
int index = 0;
char array[1000];
while(index < 1000){
array[index] = '0';
index++;
}
printf("Please enter a phrase: ");
index = 0;
do {
scanf("%c", &array[index]);
} while(array[index] != '\n' && index++ < 1000);
index = 0;
while(index < 1000)
printf("%c", array[index++]);
}
I think your looking for this:
#include<stdio.h>
int main() {
char array[1000];
printf("Please enter a phrase: ");
scanf ("%[^\n]%*c", array);
printf("\n%s", array);
return 0;
}
How can I read six digits separately, and then append them?
For example:
I want to enter the following digits: 2 3 6 , 7 5
And the expected output would be: "236,75".
I have to do it with only one loop (to read the numbers), and I have to read the numbers with the type char.
Here's what I have so far:
#include <stdio.h>
int main()
{
char c;
char string [6];
printf("Introduce a number\n");
int i = 0;
while (i <=5) {
scanf("%c", &c);
string[i] = c;
i++;
}
printf("%c\n",string);
}
Try something like this:
char string [7];
printf("Introduce a number\n");
int i = 0;
while(i <=5){
scanf("%c", &c);
string[i] = c;
i++;
}
string[i] = '\0';
//printf("%s", string);
I added the '\0' character at string[6], just in case you need that for printing the values for example.
Also, I recommend you to read about cleaning the input buffer when obtaining input from stdin. Hope it helps.
For starters ensure that your int main() is actually returning an integer.
#include <stdio.h>
int main()
{
char c;
char string[7];
char* stringy = string;
printf("Introduce a number\n");
int i = 0;
while (i <=5) {
scanf("%c", &c);
string[i] = c;
i++;
}
string[i] = '\0';
printf("%s\n",stringy);
return 0;
}
Also you want to print your entire string out with a %s format specifier. This also means that you'll need to null terminate your string which can be done by setting the last character in your array to \0.
Also make sure your array has 7 indexes instead of 6, so everything can fit.
#include <stdio.h>
int main()
{
char c;
char string [7];
printf("Introduce a number\n");
int i = 0;
while (i <=5) {
scanf("%c\n", &c);
string[i] = c;
i++;
}
string[i] = '\0';
printf("result: %s\n",string);
return 0;
}
C strings end with a null character, that is '\0'. Therefore you should always append the null character to a character string as the last character since it determines the end of the string. Therefore the line string[i] = '\0'; is necessary (at the end of the while loop, the value of i will be 6, thus pointing to the last element of the character array).
Another correction to your code is the final printf(). You specified the format to be character format ("%c"), which will only output the first character of the string. You should change it to "%s" for printing the whole string.
This program should work since it is a valid C code. If you are having troubles with this code, then it is platform specific. I couldn't run this code on VS2012, but managed to run it on a GNU C Compiler. Try running the code on an online C compiler, it should work just fine.