I am currently reading several values one after another from a file like so:
Code: ifstream f;
double x;
double a, b, c, d;
f.read((char *)&x, sizeof (double));
a = x;
f.read((char *)&x, sizeof (double));
b = x;
//etc ... for several other values Question:
How can I read every (lets say) 3rd value instead of every next value from the file
I'm currently working on a program that writes an array of struct to a file and then read back the data from the file to another array of struct. At the bottom is an image of my result.
My goal is to end up with two identical struct arrays but my program fails to do this. My struct have to members: ID and kind (of animals in this case). I declare my first arraystruct africa[] with "monkey" and "giraffe" with their respectively IDnr: 112 and 555. I stream this data to a file and read read them back to the arraystruct get_animal[]. Simply I want the get_animal[] to be identical with the africa[] when the program is over, but that is not so. According to my result(bottom image) it display:
112, monkey (get_animal[0])
112, monkey (get_animal[1])
meaning that get_animal[0] is identical to africa[0] get_animal[1] is also identical to africa[0]
but why? I want get_animal[1] to be identical with africa[1]. meaning I want the result to look like this:
112, monkey
555, giraffe
I've also made the program to print the parameters of my fwrite/fread calls. Why is the 3rd parameter = 1 meaning that only 1 element will be read/written when my program just read/write 2 elements?
Code:
main(){
FILE *fp;
struct animals
{
int id;
char kind[20];
} africa[1] = {{112,"monkey"}, {555,"giraffe"}};
}
[code]....
I am trying to write a function to reverse a wav file. The idea is to copy the header as it is from the begening of the input.wav file to the beginning of the output.wav file. After that i have to take count number of bytes(count = numberChannels * bitsPerSample in the wav i use this is 2*16= 32 bits, 32/8 = 4 bytes). With this code i am trying to copy the header( that's working fine) and then copy 10 samples from the end and put them to the output.wav file(after header not at the beginning).
This is the content of the input file:
The last 4 bytes of the header are bolded.
Code:
52 49 46 46 24 bd 01 00 57 41 56 45 66 6d 74 20
10 00 00 00 01 00 02 00 44 ac 00 00 10 b1 02 00
04 00 10 00 64 61 74 61 00 bd 01 00 00 10 00 10
ff 00 10 00 00 10 00 10 00 00 ff 10 10 10 00 10
00 00 00 10 10 10 10 00 00 00 10 00 10 00 10 ff
00 10 00 00 10 00 ff 00
This is the content of the output file it suppose to have in my example
Code:
52 49 46 46 24 bd 01 00 57 41 56 45 66 6d 74 20
10 00 00 00 01 00 02 00 44 ac 00 00 10 b1 02 00
04 00 10 00 64 61 74 61 00 bd 01 00 10 00 ff 00
00 10 00 00 10 00 10 ff 00 00 10 00 10 10 10 00
00 00 00 10 10 10 00 10 00 00 ff 10 00 10 00 10
ff 00 10 00
Code:
void reverse(char **array) {
int i=0;
word numberChannels;//word is unsigned short int , byte is unsigned char
word bitsPerSample;
[Code] .....
The problem is that (having in mind per sample is 4 bytes) instead of copying 40 bytes it just copies 20
I do not understand how I can implement this.If fread != to at least 8 bytes then do THIS: printf (" your file is near the end of file", fread result);
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#include <stdio.h>
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int i=0;
[Code] ....
I keep getting this warning message and I do not know how to fix it. Is it because I'm using char to instead of strings to replace all 't' with 'lp'?
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#include<string>
#include <stdio.h>
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char * scanf(char * a) {
[code]....
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rhhrkkj$hghjhdf$ddfkrjt
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In my implementation file
void NewString::ReplaceChar(const char& target,const char& entry)
{
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};
Main program
#include "NewString.h"
using namespace ...;
int main()
[Code].....
Instead of replacing the the l's with y's it outputted a long string of y's. Also, NewString is derived from the string class (it's for the assignment). the header and whole implementation file, already tested.
I've also tried, instead, to use a for loop in ReplaceChar() but I need to overload the == operator and I don't know how I should exactly:
bool NewString::operator ==(const char& target)const {
if(*this == target)
return true;
[Code]....
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Can we do this :
Code:
char strings[][100]={"ABC","EFG","IJK","LKM"};
char temp[100];
temp=strings[1];
I'm trying to get the int value of each character in a string and then add them all together so I can do a 1's complement of the total value. I'm trying to do simple checkum kinda of thing for verification of data.
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unsigned int stage = 1;
void controls()
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[Code]....
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Code: string str ("Hello world!");
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Code:
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{
[Code].....
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Code:
#include <stdio.h>
struct entry
{
[Code].....
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I don't know how to do this ....
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example:
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Code:
#include <stdlib.h>
int main ()
{
FILE * pFile;
int c;
pFile=fopen ("de3.txt","r");
if (pFile==NULL) perror ("Error opening file");
else
[Code]...
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insert
Code:
#include <stdio.h>
main()
{
char c1, c2;
printf("Letter 1: ");
c1 = getchar();
[Code]....
Code:
char value;
printf_s("enter:");
if (scanf_s("%c", &value) != 1)
{
printf_s("oppppssss
");
}
else
{
printf_s("ok");
}
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Code:
char * arg;
// set arg some string...
char first_[25];
char * first;
int length;
length=strlen(arg);
for (n++; arg[n] != '}' || n>=length-1; n++)
strcpy(first,arg[n]); // first += arg[n]; I have strcpy(first,arg[n]); but arg[n] is char and strcpy expects char * ;
how to solve this?
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For example lets say I have a string called str=[Hello]. I want to display the third letter so just the "l". Here's what I have so far:
Code:
#include<stdio.h>
int main() {
char str[50] = "Hello";
printf("The third letter is : %s
",str[3]);
return 0;
}
