127 lines
4.6 KiB
C
127 lines
4.6 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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void encode(char message[], char code_char[]) {
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char alphabet[52] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};
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int code[strlen(code_char)];
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for (int i = 0; i < strlen(code_char); i++) {
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for (int j = 0; j < 26; j++) {
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if (alphabet[j] == code_char[i] && code_char[i] != ' ' && code_char[i] != ',' && code_char[i] != '.') code[i] = j+1;
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}
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}
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// for (int i = 0; i < strlen(code_char); i++) printf("%d ", code[i]); printf("\n");
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for (int i = 0, k = 0; i < strlen(message); i++) {
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for (int j = 0; j < 26; j++) {
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if (alphabet[j] == message[i]) {
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if (k >= strlen(code_char)) k = 0;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j+code[k]];
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// printf("%c\n", message[i]);
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k++;
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} else {
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k++;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j+code[k]];
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// printf("%c\n", message[i]);
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k++;
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} else {
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k++;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j+code[k]];
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// printf("%c\n", message[i]);
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k++;
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}
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}
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}
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break;
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}
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}
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}
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printf("Encoded with repeating shifts ");
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for (int i = 0; i < strlen(code_char); i++) {
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if (1 <= code[i] && code[i] <= 26) printf("%d ", code[i]);
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}
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printf(": %s\n", message);
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}
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void decode(char message[], char code_char[]) {
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char alphabet[52] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};
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int code[strlen(code_char)];
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for (int i = 0; i < strlen(code_char); i++) {
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for (int j = 0; j < 26; j++) {
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if (alphabet[j] == code_char[i] && code_char[i] != ' ' && code_char[i] != ',' && code_char[i] != '.') code[i] = j+1;
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}
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}
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// for (int i = 0; i < strlen(code_char); i++) printf("%d ", code[i]); printf("\n");
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for (int i = 0, k = 0; i < strlen(message); i++) {
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for (int j = 26; j < 52; j++) {
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if (alphabet[j] == message[i]) {
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if (k >= strlen(code_char)) k = 0;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j-code[k]];
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// printf("%c\n", message[i]);
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k++;
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} else {
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k++;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j-code[k]];
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// printf("%c\n", message[i]);
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k++;
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} else {
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k++;
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if (1 <= code[k] && code[k] <= 26) {
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// printf("%c = ", message[i]);
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message[i] = alphabet[j-code[k]];
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// printf("%c\n", message[i]);
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k++;
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}
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}
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}
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break;
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}
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}
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}
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printf("Encoded with repeating shifts ");
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for (int i = 0; i < strlen(code_char); i++) {
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if (1 <= code[i] && code[i] <= 26) printf("%d ", code[i]);
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}
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printf(": %s\n", message);
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}
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int main() {
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char ar[1000];
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char code[1000];
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char option_char;
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printf("Enter the message\n");
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scanf("%[^\n]", &ar);
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int option = -1;
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printf("Encode or decode? 0 or 1 and the code word/sentence\n");
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scanf("%d %[^\n]", &option, &code);
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switch (option) {
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case 0:
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encode(ar, code);
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option = -1;
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break;
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case 1:
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decode(ar, code);
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option = -1;
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break;
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}
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} |