I am new to c programming language. I am trying to reverse elements in char array. Actually, I almost reversed but there is something that I can't make it. Here is code:
void q2_reverseTheArray(char word[100]){
int lentgh=sizeof(word);
int j;
for(j=length+1; j>=0; j--){
printf("%c", word[j]);
}
The code reverse the array but it adds another letter.
here you have a working example:
#include <stdio.h> // printf
#include <stdlib.h> // malloc, free
#include <string.h> // strlen
int main() {
char* s = "hello";
size_t l = strlen(s);
char* r = (char*)malloc((l + 1) * sizeof(char));
r[l] = '\0';
int i;
for(i = 0; i < l; i++) {
r[i] = s[l - 1 - i];
}
printf("normal: %s\n", s);
printf("reverse: %s\n", r);
free(r);
}
your code was wrong in length + 1 it should say length - 1.
and you have to pay attention to the terminating '\0'.
The correct code is
for(j=length-1; j>=0; j--){
printf("%c", word[j]);
This is because the string's elements are indexed from 0 to length-1. For example,
word == "Hello"
length == 5
word[0] == 'H'
word[1] == 'e'
word[2] == 'l'
word[3] == 'l'
word[4] == 'o'
strcpy(word, "Look at Sky"} insteadIn my experience, using strlen() instead of sizeof() is better as it removes the need to modify the result in any way, like in my example:
char *c;
int i;
scanf("%s", c);
for (i = strlen(c); i >= 0; --i) {
printf("%c", c[i]);
}
Without string.h header file
main()
{
char str1[100], str2[100];
int i, k, j;
scanf("%s", &str1);
for(i=0; str1[i] != '\0'; i++ );
j=i-1;
for(k=0; k<=i; k++)
{
str2[k]=str1[j];
j--;
}
for(k=0; k<i; k++)
printf("%c", str2[k]);
return 0;
}
length; then it should crash because you start the loop by accessingword[length + 1]which is 2 indices out of range.for (j=length-1; j>0; j--)This will start at the last character and repeat until the first one. Better yet, become accustomed to using your debugger.