dynamic_list

#include <stdio.h>
#include <math.h>

struct Node {
    Node* prev = 0;
    int year;
    int ussr;
    int usa;
    int uk;
    int fr;
};

struct queue {
    Node* beg;
    Node* end;
    int size;
};

void init(queue& qu);

void push(queue& qu, int year, int ussr, int usa, int uk, int fr);

void pop(queue& qu);

void clear(queue& qu);

int input_check();

void input(int& count, queue& qu);


int main() {
    /*
    years = {1928, 1940, 1950, 1955}
    ussr = {120, 422, 580, 837}
    usa = {137, 166, 209, 250}
    uk = {94, 105, 122, 139}
    fr = {105, 114, 131, 172}
    */

    queue qu;
    init(qu);

    ///////////////////// inputing table /////////////////////

    int count = 5;
    input(count, qu);


    ///////////////////// part A /////////////////////

    Node* pos = qu.beg;
    Node* max = pos;
    int diff = abs( pos->uk  - pos->fr);
    pos = qu.beg -> prev;
    for (int i = 1; i < qu.size; ++i) {

        if (abs(pos->uk - pos->fr) > diff) {
            max = pos;
            diff = abs(pos->uk - pos->fr);
        }
        pos = pos -> prev;
    }
    printf("Год: %d\nПроцент роста Англии: %d\nПроцент роста Франции: %d\nРазница: %d\n\n", max->year, max->uk, max->fr, diff);


    ///////////////////// part B /////////////////////

    int growth;
    printf("Введите темп роста производительнсоти в США:\n");
    scanf("%d", &growth);

    pos = qu.beg;
    for (int i = 0; i < qu.size; ++i) {
        if (pos->usa <= growth) {
            printf("Год:%d ========== Процент роста:%d\n", pos -> year, pos->usa);
        }
        pos = pos -> prev;
    }

    clear(qu);
    return 0;
}


void init(queue& qu) {              //initializing queue
    qu.size = 0;
    qu.beg = 0;
    qu.end = 0;
}

void push(queue& qu, int year, int ussr, int usa, int uk, int fr) {
    Node* pv = new Node;            //new field (equals to string in table)

    pv -> year = year;              //pushing data
    pv -> ussr = ussr;
    pv -> usa = usa;
    pv -> uk = uk;
    pv -> fr = fr;

    ////////////////organizing queue//////////////////

    if (!qu.size) {                 //pushing when size = 0
        qu.beg = pv;
    } else if (qu.size > 0) {       //pushing when size > 0
        qu.end -> prev = pv;
    }
    qu.end = pv;
    ++qu.size;
}

void pop(queue& qu) {
    if (qu.size) {                  // size > 0
        Node* pv = qu.beg;
        qu.beg = qu.beg -> prev;
        printf("%d\n", pv -> year); //printing deleted year
        delete pv;
        --qu.size;
        if (!qu.size) {             //reiniting in case of deleting every field
            init(qu);
        }
    }
}

void clear(queue& qu) {
    if (qu.size) {
        int size = qu.size;
        for (int i = 0; i < size; ++i) {
            Node* pv = qu.beg;
            qu.beg = qu.beg -> prev;
            delete pv;
            --qu.size;
        }
    }
    init(qu);
}

int input_check() {

    int data;
    int len = 0;
    char ch;
    char* str = (char*)malloc(sizeof(char));
    //printf("Input:\n");
    while (1) {

        ch = getchar();
        if (ch == '\n') {
            break;
        } else {
            str[len] = ch;
            str = (char*)realloc(str,(1 + (++len)*sizeof(char)));
        }

    }

    //printf("Str: %s", str);
    data = atoi(str);
    if (!len) {
        return -2;
    }
    if (data == 0 && str[0] != '0') {
        return -1;
    } else if (data < 0) {
        return -3;
    } else {
        return data;
    }

}

void input (int& count, queue& qu) {

    int     year,
            ussr,
            usa,
            uk,
            fr;
    int* data;


    while (count > 0) {

        switch (count) {

            case 5:
                printf("Введите год:\n");
                data = &year;
                break;
            case 4:
                printf("Введите темпы роста СССР в процентах:\n");
                data = &ussr;
                break;
            case 3:
                printf("Введите темпы роста США в процентах:\n");
                data = &usa;
                break;
            case 2:
                printf("Введите темпы роста Англии в процентах:\n");
                data = &uk;
                break;
            case 1:
                printf("Введите темпы роста Франции в процентах:\n");
                data = &fr;
                break;
        }

        *data = input_check();

        if (*data == -2 && count%5 == 0) {

            //printf("Konez\n");
            break;

        } else if (*data < 0) {

            printf("Vvedite eshe raz\n");
            continue;

        } else {

            //printf("Data: \n");
            if (count == 1) {

                count = 5;
                push(qu, year, ussr, usa, uk, fr);
                //printf("Year: %d, Ussr: %d, Usa: %d, Uk: %d, Fr: %d\n", qu.beg->year, qu.beg->ussr, qu.beg->usa, qu.beg->uk, qu.beg->fr );

            } else {
                --count;
            }

        }

    }

}