laba2

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <ctype.h>
void menu() {
    char R1 = ' ';
    char R2 = ' ';
    //int Xstart = 0; скорее всего здесь другой тип
    //int Xend = 0;
    //int deltaX = 0;
    int flag = 0;
    char radius = ' ';
    char k = ' ';
    printf("Laba №2,  nomer variant\n");
    printf(" name/surname");
    while (1 == 1) {

        if (flag == 0) {
            printf("Input R1:\n");
            scanf_s("%c", &R1);
            fflush(stdin);
            if ((!isdigit(R1)) || (R1 <= 0)) {
                printf("Wrong input parameter, {Radius should be greater than zero and should be a digit}. Type ‘y’ for repeat, or any other for exit from application\n");
                system("pause");
                scanf_s("%c", &k);
                fflush(stdin);
                if (k == 'y') {
                    flag = 1;
                    continue;
                }
                else {
                    flag = 0;
                    continue;
                }
            }
            else{
                flag = 0;
                radius = atoi(&R1);

            }



    }

    }

}
int main(void) {

    menu();
    return 0;
}