如何将数组值复制到另一个数组

Question

I have two arrays:

char roundNames1[16][25], roundNames2[16 / 2][25];

I then want to copy a result from the first array to the second. I have tried this:

where roundNames1[5] = "hello"

#include <string.h>

printf("First array: %s", roundNames1[5]);
strcpy(roundNames1[5], roundNames2[6]);
printf("Second array: %s", roundNames2[6]);

But this just returns

First array: hello
Second array:

Why is it not working?

Answer 1

You need to exchange arguments of function strcpy

strcpy( roundNames2[8], roundNames1[5] );

Here is a part pf the function description from the C Standard

7.23.2.3 The strcpy function

Synopsis

1

#include <string.h>
char *strcpy(char * restrict s1, const char * restrict s2);

Description

2 The strcpy function copies the string pointed to by s2 (including the terminating null character) into the array pointed to by s1. If copying takes place between objects that overlap, the behavior is undefined.

Answer 2

strcpy - arguments other way around.

http://www.cplusplus.com/reference/cstring/strcpy/

Answer 3

Copy arrays/strings with memcpy

void * memcpy (void * destination, void * source, size_t size)

The memcpy function copies an certain amount of bytes from a source memory location and writes them to a destinaction location.

Example:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void main()
{
    char a[] = "stackoverflow";
    int s = sizeof(a);
    int c = s / sizeof(a[0]);
    char *p = malloc(s);
    memcpy(p, &a, s);
    printf("%s\n", p);
    free(p);
}

Output

$ ./a.out 
stackoverflow