Latest random crap.

1 files changed, 121 insertions, 0 deletions

diff --git a/foursquare.c b/foursquare.c
new file mode 100644
index 0000000..9552ed4
--- /dev/null
+++ b/foursquare.c
@@ -0,0 +1,121 @@
+// foursquare.c
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define Q ('Q'-'A')
+
+typedef struct vec2 {
+    int x;
+    int y;
+} Vec2;
+
+int increinc(int *);
+void allupper(char *);
+void genkey(char *, char *);
+Vec2 *newVec2(const int, const int);
+
+int main(int argc, char **argv)
+{
+    int x, y, c=0;
+
+    if(argc!=4){
+        printf("Usage: %s <key1> <key2> <cipher>", *argv);
+        exit(1);
+    }
+
+    printf("%s, %s ", *(argv+1), *(argv+2));
+
+    char *trkey = *(argv+1);
+    allupper(trkey);
+    char *trfullkey = malloc(26);
+    genkey(trkey, trfullkey);
+
+    char *blkey = *(argv+2);
+    allupper(blkey);
+    char *blfullkey = malloc(26);
+    genkey(blkey, blfullkey);
+
+    char *cipher = *(argv+3);
+    allupper(cipher);
+
+    int i=0;
+    Vec2 *trtable[25];
+    for(x=0; x<5; x++)
+        for(y=0; y<5; y++)
+            trtable[trfullkey[i++]-'A'] = newVec2(x, y);
+    free(trfullkey);
+
+    i = 0;
+    Vec2 *bltable[25];
+    for(x=0; x<5; x++)
+        for(y=0; y<5; y++)
+            bltable[blfullkey[i++]-'A'] = newVec2(x, y);
+    free(blfullkey);
+
+    char basetable[5][5];
+    for(x=0; x<5; x++)
+        for(y=0; y<5; y++){
+            if(c==Q)
+                c++;
+            basetable[x][y] = 'A' + c++;
+        }
+
+    for(i=0; i<strlen(cipher)/2; i++){
+        char c1 = cipher[2*i];
+        char c2 = cipher[2*i+1];
+
+        putchar(basetable[trtable[c1-'A']->x][bltable[c2-'A']->y]);
+        putchar(basetable[bltable[c2-'A']->x][trtable[c1-'A']->y]);
+    }
+    putchar('\n');
+
+    for(i=0; i++; i<25){
+        free(trtable[i]);
+        free(bltable[i]);
+    }
+
+    return 0;
+}
+
+int increinc(int *num)
+{
+    (*num)++;
+    return (*num)++;
+}
+
+void allupper(char *input)
+{
+    int i;
+    for(i=0; i<strlen(input); i++)
+        if(isalpha(input[i]))
+            input[i]=toupper(input[i]);
+}
+
+void genkey(char *input, char *output)
+{
+    int dict[26];
+    memset(dict, 0, 26*sizeof(int));
+
+    int i, outpt = 0;
+    for(i=0; i<strlen(input); i++){
+        if(!dict[input[i]-'A']){
+            output[outpt++]=input[i];
+        }
+        dict[input[i]-'A'] += 1;
+    }
+
+    for(i=0; i<26; i++)
+        if(!dict[i] && i!=Q)
+            output[outpt++]=i+'A';
+    output[outpt]='\0';
+}
+
+Vec2 *newVec2(const int x, const int y)
+{
+    Vec2 *v = malloc(sizeof(Vec2));
+    v->x = x;
+    v->y = y;
+    return v;
+}