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--- tanszek:oktatas:techcomm:lzw_coding [2024/11/18 20:24] – [Key Steps in LZW Compression] knehez
+++ tanszek:oktatas:techcomm:lzw_coding [2024/11/19 07:54] (current) – knehez
@@ Line 124: / Line 124: @@
+C implementation of LZW encoding:
+<sxh c>
+#include <stdio.h>
+#include <string.h>
+#define MAX_sxhS 100
+char sxhTable[MAX_sxhS][10] = {"a","b","c","d","e"};
+int tableElements = 5;
+int isInsxhTable(char *s)
+{
+    for(int i = 0; i < tableElements; i++)
+    {
+        if(strcmp(sxhTable[i], s) == 0)
+        {
+            return i;
+        }
+    }
+    return -1;
+}
+int main()
+{
+    char text[] = "dabbacdabbacdabbacdabbacdee";
+    char *p = text;
+    int bufferEnd = 1;
+    int lastFoundIndex = -1;
+    while(*p != '\0')
+    {
+        char subStr[10];
+        strncpy(subStr, p, bufferEnd);
+        subStr[bufferEnd] = '\0';
+        int foundIndex = isInsxhTable(subStr);
+        if(foundIndex != -1)
+        {
+           bufferEnd++;
+           lastFoundIndex = foundIndex;
+           continue;
+        }
+        p += strlen(subStr) - 1;
+        bufferEnd = 1;
+        strcpy(sxhTable[tableElements++], subStr);
+        printf("%d,", lastFoundIndex + 1);
+    }
+}
+</sxh>