Program optimization

I have quite a few places in my program where input from the user is required. I want the user to be able to press q at anytime, so that they go back to the beginning of the program (where there is a little menu, and the whole things starts again. You can see in the program where i have an if statement, trying to do this, but it is not a solution for any point in the program.

Any ideas?

Code:

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <Windows.h> int main() { char *options[100], *as[100], *bs[100], *cs[100], *Xos[100], *Yos[100], *Zos[100], *filename[20];//the s at the end of the name tell me it is stored as a string. float a, b, c, Xo, Yo, Zo; FILE *recentdata, *EulerData;//pointer to store recent data in text file. while (1) { menu(); scanf("%99s", options); //What to do if user types exit if(strcmpi(options,"exit") == 0)//compare options to "recent" NOT case sensitive. { exit(0); } //What to do if user types q else if(strcmpi(options,"q") == 0)//compare options to "recent" NOT case sensitive. { system("cls"); } //What to do if user types recent else if(strcmpi(options,"recent") == 0)//compare options to "recent" NOT case sensitive. { recentdata = fopen("recentdata.txt", "r"); fscanf (recentdata, "%s %s %s %s %s %s", as, bs, cs, Xos, Yos, Zos); fclose; } //if the user didnt type recent, they typed something else in...? else { strcpy(as,options);//copy the value of options into as. scanf("%99s", bs); scanf("%99s", cs); printf ("%s %s %s\n\n", as, bs, cs); printf("Please input Xo, Yo and Zo\n"); scanf("%99s", Xos); scanf("%99s", Yos); scanf("%99s", Zos); printf ("%s %s %s\n\n", Xos, Yos, Zos); recentdata = fopen("recentdata.txt", "w"); fprintf(recentdata, "%s %s %s %s %s %s\n", as, bs, cs, Xos, Yos, Zos); fclose; } a=atof(as); //converting strings to floats so that the compiler understands it is a number that can be used mathematically. b=atof(bs); c=atof(cs); Xo=atof(Xos); Yo=atof(Yos); Zo=atof(Zos); printf (" a = %.2f\n b = %.2f\n c = %.2f\nXo = %.2f\nYo = %.2f\nZo = %.2f\n", a, b, c, Xo, Yo, Zo); printf("Beginning execution of improved Euler...\n\n"); Sleep(1000); printf("Please enter the name of the file to store the data in\n"); printf("If it doesnt exist, it will be created.\n\n"); scanf("%s", filename); printf("\nStoring all Data in file '%s.txt'\n", filename); Sleep(1000); } return 0; } int menu() { printf("Type 'recent' to use the last entered data or:\nInput a, b and c, hitting Enter between each one,\n"); printf("Typing 'q' at any time will bring you back here,\n"); printf("To exit the program, from this screen type 'exit'.\n"); return(1); }