[SPCA] Finish arrays, strings, some fixes

semester3/spca/code-examples/00_c/03_arrays.c

@@ -11,5 +11,10 @@ int main( int argc, char *argv[] ) {
     printf( "%d\n", *( data + 5 ) ); // equivalent as above
     int multidim[ 5 ][ 5 ];          // 2-dimensional array
                                      // We can iterate over it using two for-loops
+    int init_array[ 2 ][ 2 ] = {
+        {1, 2},
+        {3, 4}
+    };                       // We can initialize an array like this
+    int empty_arr[ 4 ] = {}; // Initialized to 0
     return 0;
 }

semester3/spca/code-examples/00_c/04_strings.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <string.h>
+
+int main( int argc, char *argv[] ) {
+    char hello[ 6 ] = "hello";                           // Using double quotes
+    char world[ 6 ] = { 'w', 'o', 'r', 'l', 'd', '\0' }; // As array
+
+    char src[ 12 ], dest[ 12 ];
+    strncpy( src, "ETHZ", 12 );     // Copy strings (extra elements will be set to \0)
+    strncpy( dest, src, 12 );       // Copy strings (last arg is first n chars to copy)
+    if ( strncmp( src, dest, 12 ) ) // Compare two strings. Returns 1 if src > dest
+        printf( "Hello World" );
+    strncat( dest, " is in ZH", 12 ); // Concatenate strings
+    return 0;
+}