arpruss
diff --git a/‎decode.c‎
Lines changed: 110 additions & 0 deletions b/‎decode.c‎
Lines changed: 110 additions & 0 deletions
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+#include <stdint.h>
+#ifdef TEST
+#include <stdio.h>
+#endif
+
+//#pragma bank 3
+#include "encoded.h"
+
+uint8_t decodeInt(const uint8_t* blob, uint32_t* valueP) {
+    if (blob[0] & 0x80 ) {
+        *valueP = blob[0] & 0x7F;
+        return 1;
+    }
+    else if (blob[1] & 0x80) {
+        *valueP = blob[0] | ((uint32_t)(blob[1]&0x7F)<<7);
+        return 2;
+    }
+    else /* if (blob[2] & 0x80) */ {
+        *valueP = blob[0] | ((uint32_t)(blob[1])<<7) | ((uint32_t)(blob[2]&0x7F)<<14);
+        return 3;
+    }    
+}
+
+void decodeWord(uint8_t start, uint32_t nextFour, char* buffer) {
+    buffer[0] = start + 'A';
+    buffer[1] = ((uint8_t)(nextFour >> 15) & 0x1F) + 'A';
+    buffer[2] = ((uint8_t)(nextFour >> 10) & 0x1F) + 'A';
+    buffer[3] = ((uint8_t)(nextFour >> 5) & 0x1F) + 'A';
+    buffer[4] = ((uint8_t)(nextFour) & 0x1F) + 'A';
+    buffer[5] = 0;
+}
+
+void getWord(uint16_t n, char* buffer) {
+    uint16_t count = 0;
+    uint8_t i;
+    for (i = 0 ; i < 26 && n >= words[i+1].wordNumber ; i++) ;
+    if (i == 26) {
+        *buffer = 0;
+        return;
+    }
+    n -= words[i].wordNumber;
+    uint32_t word = 0;
+    const uint8_t* blob = wordBlob + words[i].blobOffset;
+    uint16_t j;
+    for (j=0; j<=n; j++) {
+        uint32_t delta;
+        blob += decodeInt(blob, &delta);
+        word += delta + 1;
+    }
+    decodeWord(i, word, buffer);
+}
+
+uint8_t filterWord(char* s) {
+    for (int i=0; i<5; i++)
+        if (s[i] < 'A' || s[i] > 'Z')
+            return 0;
+    uint8_t i = s[0]-'A';
+    uint32_t w = ((uint32_t)(s[1]-'A') << 15) | ((uint32_t)(s[2]-'A') << 10) | ((uint32_t)(s[3]-'A') << 5) | (uint32_t)(s[4]-'A');
+    uint16_t n = words[i+1].wordNumber - words[i].wordNumber;
+    uint32_t match = 0;
+    const uint8_t* b = wordBlob + words[i].blobOffset;
+    for (uint16_t j=0; j<n; j++) {
+        uint32_t delta;
+        b += decodeInt(b, &delta);
+        match += delta + 1;
+        if (match > w)
+            return 0;
+        else if (match == w)
+            return 1;
+    }
+    return 0;
+}
+
+void getSpecialWord(int16_t n, char* buffer) {
+    uint16_t w = 0;
+    const uint8_t* b = answers;
+    while(n>=0) {
+        uint8_t c = *b;
+        if (c == 0) {
+            w += 8;
+        }
+        else {
+            for (uint8_t i = 0 ; i < 8 ; i++) {
+                if (c & 1) {
+                    n--;
+                    if (n<0)
+                        break;
+                }
+                w++;
+                c >>= 1;
+            }
+        }
+        b++;
+    }
+    getWord(w, buffer);
+}
+
+#ifdef TEST
+main() {
+    char w[6] = {0};
+    for (int i=0; i<100; i++) {
+        getSpecialWord(i, w);
+        puts(w);
+    }
+    printf("%d\n", filterWord("SEREZ"));
+    printf("%d\n", filterWord("SERER"));
+    printf("%d\n", filterWord("ZYMIC"));
+    printf("%d\n", filterWord("BAAED"));
+}
+#endif