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    <p>Without having more of your source posted, it looks and sounds like you are confusing arrays and strings.</p> <p>In C and C++ a 'char' is an 8-bit value that is usually used to store an ASCII character. The ASCII table is like the periodic table, it provides a numbered list of things so that you can refer to them numerically. 1 in the periodic table is Hydrogen, it is element 1. In ASCII the value 32 represents the space character, the value 48 represents the '0' character, 49 represents '1'.</p> <p>In C and C++ the convention is that if a sequence of characters are supposed to be treated as a string, they must end with a character that has the ASCII value of 0 (not '0', but 0, also written '\0').</p> <p>So store a 3-character string, you need 4 chars or bytes.</p> <pre><code>char foo[3] = "foo"; // illegal. "foo" is actually { 'f', 'o', 'o', 0 }; char bar[4] = "foo"; // ok </code></pre> <p>Because your arrays appear to be char-arrays and not strings, you cannot use "strcpy" etc, you must use "memcpy" or copy elements by hand.</p> <p>Here is a working version of the problem you are trying to solve, hope this helps.</p> <p>Online demo at ideone: <a href="http://ideone.com/6TcapX" rel="nofollow">http://ideone.com/6TcapX</a></p> <pre><code>#include &lt;stdio.h&gt; #include &lt;string.h&gt; #define MAZE_COLUMNS 3 #define MAZE_ROWS 3 #define MAZEW_COLUMNS 4 #define MAZEE_COLUMNS 4 static void transcribeMazeRow(const char* source, size_t srcColumns, char prefix, char* dest, size_t destColumns) { dest[0] = prefix; memcpy(&amp;dest[1], &amp;source[0], srcColumns * sizeof(source[0])); } int main(int argc, char* argv[]) { // 3 rows of 3 columns, each is a distinct char. this is not a string. char maze[MAZE_ROWS][MAZE_COLUMNS] = { { 'a', 's', 'd' }, { 'u', 's', 'd' }, { 'p', 's', 'd' } }; // 3 rows of 4 columns, distinct character values, not a string. char mazeW[MAZE_ROWS][MAZEW_COLUMNS]; char mazeE[MAZE_ROWS][MAZEE_COLUMNS]; for (size_t row = 0; row &lt; MAZE_ROWS; ++row) { transcribeMazeRow(maze[row], MAZE_COLUMNS, 'W', mazeW[row], MAZEW_COLUMNS); transcribeMazeRow(maze[row], MAZE_COLUMNS, 'E', mazeE[row], MAZEE_COLUMNS); } // this part is mostly to show the poster the correct way to refer to all elements of each array. printf("maze: %c%c%c, %c%c%c, %c%c%c\n", maze[0][0], maze[0][1], maze[0][2], maze[1][0], maze[1][1], maze[1][2], maze[2][0], maze[2][1], maze[2][2] ); printf("mazeW: %c%c%c%c, %c%c%c%c, %c%c%c%c\n", mazeW[0][0], mazeW[0][1], mazeW[0][2], mazeW[0][3], mazeW[1][0], mazeW[1][1], mazeW[1][2], mazeW[1][3], mazeW[2][0], mazeW[2][1], mazeW[2][2], mazeW[2][3] ); printf("mazeE: %c%c%c%c, %c%c%c%c, %c%c%c%c\n", mazeE[0][0], mazeE[0][1], mazeE[0][2], mazeE[0][3], mazeE[1][0], mazeE[1][1], mazeE[1][2], mazeE[1][3], mazeE[2][0], mazeE[2][1], mazeE[2][2], mazeE[2][3] ); return 0; } </code></pre> <p>Output:</p> <pre><code>maze: asd, usd, psd mazeW: Wasd, Wusd, Wpsd mazeE: Easd, Eusd, Epsd </code></pre>
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    1. COI had got a complier waring regarding character array and string mixup but I never knew of **memcpy** until now
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