1 files changed, 37 insertions, 0 deletions
diff --git a/set1/task4.c b/set1/task4.c
new file mode 100644
index 0000000..c95e21f
--- /dev/null
+++ b/set1/task4.c
@@ -0,0 +1,37 @@
+
+#include "../lib/lib.h"
+
+int main() {
+	/** read the file */
+	FILE *fp;
+	int malloc_size = 62;
+	int line_number = 0;
+	int j;
+	char key;
+	char *string = malloc(malloc_size);
+	char *string2 = malloc(malloc_size);
+	char *cleartext = malloc(malloc_size);
+	struct key_and_freq tmp;
+
+	fp = fopen("4.txt", "r");
+
+	if (fp == NULL) {
+		printf("Error open file\n");
+		exit(1);
+	}
+	
+	while (fscanf(fp, "%61c", string) != EOF) {
+		tmp.hits = 0;
+		j = decode_hex_string(string, string2);
+		key = brute_force_single_byte_xor(string2, j, &tmp);
+		xor_string(string2, &key, cleartext, 1, j);
+		if ((!isprintable(cleartext, j)) || (tmp.hits < 10))
+			continue;
+		
+		printf("%s", cleartext);
+		line_number++;
+	}
+
+	fclose(fp);
+	return 0;
+}