#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define max_length 20

struct Rules {
    char origin[10];
    char replacement[10];
};

int Count_Length(char* line, struct Rules* rules, int number_of_rules){
    int rule_index, new_length = 0;
    while (1) {
        char* pointer = line + strlen(line) + 1;
        for (int i = 0; i != number_of_rules; ++i) {
            if (strstr(line, rules[i].origin) != NULL && strstr(line, rules[i].origin) < pointer) {
                pointer = strstr(line, rules[i].origin);
                rule_index = i;
            }
        }
        if (pointer != line + strlen(line) + 1) {
            new_length += strlen(line) - strlen(pointer) + strlen(rules[rule_index].replacement);
            line = pointer + strlen(rules[rule_index].origin);
        } else {
            new_length += strlen(line);
            break;
        }
    }
    return new_length;
}

char* Transform_Line(char* line, struct Rules* rules, int number_of_rules){
    int new_length = Count_Length(line, rules, number_of_rules);
    char* new_line = (char*)malloc(new_length * sizeof(char));
    char* current_new_line_pointer = new_line;
    int rule_index = 0;
    while (1) {
        char* pointer = line + strlen(line) + 1;
        for (int i = 0; i != number_of_rules; ++i) {
            if (strstr(line, rules[i].origin) != NULL && strstr(line, rules[i].origin) < pointer) {
                pointer = strstr(line, rules[i].origin);
                rule_index = i;
            }
        }
        if (pointer != line + strlen(line) + 1) {
            strncpy(current_new_line_pointer, line, strlen(line) - strlen(pointer));
            current_new_line_pointer += strlen(line) - strlen(pointer);
            strncpy(current_new_line_pointer, rules[rule_index].replacement, strlen(rules[rule_index].replacement));
            current_new_line_pointer += strlen(rules[rule_index].replacement);
            line = pointer + strlen(rules[rule_index].origin);
        } else {
            strcpy(current_new_line_pointer, line);
            break;
        }
    }
    printf("%s\n", new_line);
    return new_line;
}

int main() {
    int n;
    char* line;

    printf("Please enter number of rules: ");
    scanf("%d", &n);
    struct Rules* rules = (struct Rules*)(malloc(n * sizeof(struct Rules)));

    printf("Enter rules: \n");
    for (int i = 0; i != n; ++i){
        scanf("%s%s", rules[i].origin, rules[i].replacement);
    }

    printf("Enter line to transform:\n");
    scanf("%s", line);

    for (int i = 0; i != 5; ++i){
        line = Transform_Line(line, rules, n);
    }

    return 0;
}