Remove user in array Struct program - c

Question

I'm working in a struct array program to make some simple user applications. Below is a compilable code, it is not the full code, but it shows that the function to remove a user is not working. I'm new to C and I am not sure about how to do this user remotion. I thought about something related to a null array, but it didn't work. The program asks to enter the name, so the user will be removed.
#include<stdio.h>
#include <stdlib.h>
#include <string.h>
#define max_users 50
int num = 0; //variable to count the number of users
typedef struct
{
char name[50];
int age;
}user;
user number[max_users];
user aux[max_users];
user read_user()
{
user user;
printf("\nEnter your name: ");
scanf("%s", &(user.name));
printf("\nEnter your age: ");
scanf("%d",&(user.age));
return user;
}
void printUser(user user)
{
printf("\n-----------------------\n");
printf("\nName: %s", user.name);
printf("\nAge: %d", user.age);
}
void enterUser()
{
number[num] = read_user();
printUser(number[num]);
num++;
}
void printAllUsers()
{
for(int i = 0; i < num; i++)
{
printUser(number[i]);
}
}
void performUserRemotion(char name[])
{
char null[50] = {"\0"};
for (int i = 0; i < num; i++) {
if (strcmp(name, number[i].name) == 0)
{
strcpy(number[i].name, null);
printf("\n*** User removed ***");
i--;
}
else
{
printf("\n*** No user ***");
break;
}
}
}
void removeUser()
{
char name_search[50];
int i;
printf("Enter the user to be removed: ");
scanf("%s", &name_search);
performUserRemotion(name_search);
}
int main()
{
int choice;
while(1)
{
printf("\n\nRECORD: ");
printf("\n1) Enter User");
printf("\n2) Remove User");
printf("\n3) Print all users");
printf("\n4) Exit");
printf("\n\nEnter the command >> ");
scanf(" %d", &choice);
switch(choice)
{
case 1:
enterUser();
break;
case 2:
removeUser();
break;
case 3:
printAllUsers(num);
break;
case 4:
printf("\n*** Exit ***\n");
exit(0);
break;
}
}
}
In the function below I planned to remove all the information about the user, so when I enter 3) Print all users, the user removed does not appear anymore and the array is reduced by 1.
void performUserRemotion(char name[])
{
char null[50] = {"\0"};
for (int i = 0; i < num; i++) {
if (strcmp(name, number[i].name) == 0)
{
strcpy(number[i].name, null);
printf("\n*** User removed ***");
i--;
}
else
{
printf("\n*** No user ***");
break;
}
}
}
Pictures A and B are the user's registrations. Picture C is when you enter the command to remove a user, in this case, I registered 'user' and 'name' and wanted 'user' to be removed, so when I enter 3) Print all users, the screen only shows 'name'.
The program still has some basic problems, such as it can't read a name with space, but I will work on it later. The main problem is that I can't perform the remotion of a user.

Answer 1

The logic of removing a user is wrong, because when you print all users, you print the whole content of the array. So to remove a user, you must have somewhere num = num - 1;.
A simple way is to find the index of the user to remove, and then consistently erase every record with next one:
void performUserRemotion(char name[])
{
char null[50] = { "\0" };
int i;
// find the name
for (i = 0; i < num; i++) {
if (strcmp(name, number[i].name) == 0)
{
break;
}
}
if (i == num) {
printf("\n*** No user ***");
}
else {
// remove the user from the array
for (; i < num - 1; i++) {
memcpy(number + i, number + i + 1, sizeof(*number));
}
num -= 1;
printf("\n*** User removed ***");
}
}
You still have a number of minor problems like unused variables, so when everything will work, you should ask for a full review on Code Review