I am making a simple C program that would ask your age and gender. If your gender is not M or F the program will ask for a different input. If your age is less than zero, the program will require for another input. This is my code:
#include<stdio.h>
int main(){
int a;
char g;
entry:
printf("%s","AGE : ");
scanf("%d", &a);
getchar();
insert:
printf("%s","GENDER :");
scanf("%s", &g);
getchar();
while (a < 0){
goto entry;
}
switch(g){
case 'M':{
printf("I am a %d yr old male", a);break;
}
case 'F':{
printf("I am a %d yr old female", a);break;
}
default:{
goto insert; break;
}
}
return 0;
}
and this is an example of the program running
AGE : 21
GENDER :M
I am a 0 yr old male
Altough I detected a weirdness (see the large comment) in code, it outputs as you expected so you can use an approach like this:
#include<stdio.h>
#include<stdbool.h>
int main(){
int age, a;
char g;
bool validInput;
do {
validInput = true;
printf("%s","AGE : ");
scanf("%d", &age);
/*
* If you use directly the 'a' var, somehow it will not print
* input age. That's why I had to use a = age assignment.
* This is weird, if someone knows why this happens let me
* know please.
*/
a = age;
if(a < 0) {
validInput = false;
}
printf("%s","GENDER : ");
scanf("%c", &g);
getchar();
if(g != 'M' && g != 'F') {
validInput &= false;
}
} while(!validInput);
switch(g){
case 'M':
printf("I am a %d yr old male\n", a); break;
case 'F':
printf("I am a %d yr old female\n", a); break;
default:
printf("Oops! Something went wrong...\n");
}
return 0;
}