Array prints random symbols - c++

Question

I need to do a program for school that reads few products and their price and then sort them in a list accodring by their price so im using array list to do it but when i print them i get random characters as output
#include <stdlib.h>
#include <stdio.h>
int main(){
int i = 0;
char list1[7];
char list2[7];
char list3[7];
while(i <= 3){
char name;
int price;
printf("Give me the product \n");
scanf("%s", &name);
printf("Give the price \n");
scanf("%d", &price);
if(price == 1){
list1[i] = list1[i] + name;
} else if(price == 2){
list2[i] = list2[i] +name;
} else if(price == 3){
list3[i] = list3[i] +name;
} else {
printf("Invalid number! \n Give us number 1,2 or 3");
printf("Give me the product \n");
scanf("%s", &name);
("Give the price \n");
scanf("%d", &price);
}
i = i + 1;
}
for (int z = 0; z <= 3; z++){
printf("%s",list1);
printf("\n");
printf("%s",list2);
printf("\n");
printf("%s",list3);
printf("\n");
}
}

Answer 1

#include <stdlib.h>
//Need string.h library to use strcopy
#include <string.h>
#include <stdio.h>
#define MAX_CHAR_SIZE 10
int main(){
//We define the maximum size of an array to be sure it will not overflow so the maximum character that list1,2,3 can contain is 10 including '/0' since you wanna print it as a string
char list1[MAX_CHAR_SIZE];
char list2[MAX_CHAR_SIZE];
char list3[MAX_CHAR_SIZE];
char name[MAX_CHAR_SIZE];
//I prefer unsigned if you know you don't to go in negative value
unsigned int price;
//Prefer for over while if you know how many time you need to loop
for (int i = 0; i < 3; i++){
printf("Give me the product \n");
scanf("%s", name);
printf("Give the price \n");
scanf("%u", &price);
if(price == 1){
//Copy name in list 1, you can't copy an array of x char in a single case of another array, 1 case of an array = 1 char
strcpy(list1, name);
}
else if(price == 2){
strcpy(list2, name);
}
else if(price == 3){
strcpy(list3, name);
}
else {
printf("Invalid number! \n Give us number 1,2 or 3");
printf("Give me the product \n");
scanf("%s", name);
printf("Give the price \n");
scanf("%u", &price);
}
}
//No need to loop over this 3 time only 1 is enough
printf("%s \n",list1);
printf("%s \n",list2);
printf("%s \n",list3);
}
I add comment over things I changed to make the initial objectives, IDK if it's the right goal but at least you got the same character in input and output, there was many things that wasn't right in your code you simply can't add the hexadecimal value of two character together to overwrite, you got to make something like list[I] = name[I].
And in C since we don't have the string type you got to create an array of char to make one AND BE SURE TO GET THE RIGHT SIZE TO FIT '\0'.
If it's your final exam a friendly advice, train a lot.

Answer 2

Looks like you forgot printf in one of your lines. Change ("Give the price\n"); to printf("give the price\n");.

Answer 3

It should work if I understand your question
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX_LENGTH 10
int main(){
int n; //no of products
printf("Enter no. of products: ");
scanf("%d", &n);
char name[n][MAX_LENGTH]; //create multidimensional array to store namme
unsigned int price[n]; //array to store price. index will be similar to name
for (int i = 0; i < n; i++){ //Enter details
printf("Enter name: ");
scanf("%s", name[i]);
printf("Enter price: ");
scanf("%u", &price[i]);
}
int N = n;
while (N > 0){ //Run loop until index bigger than zero
char temp_string[MAX_LENGTH]; //create temporary variable
unsigned int temp_price; //to store values
int max_price_index = 0; //Index where max value is stored
for (int i = 1; i < N; i++){ //start loop from till end to search each value
if(price[i] > price[max_price_index]) //If searched value is bigger thar previous one(default at index 0)
max_price_index = i; //the replace it
}
strcpy(temp_string, name[N - 1]); //in next 7 lines name and price at max index is
strcpy(name[N - 1], name[max_price_index]); //swapped with values at index N (which is last of scope)
strcpy(name[max_price_index], temp_string);
temp_price = price[N - 1];
price[N - 1] = price[max_price_index];
price[max_price_index] = temp_price;
N--; //reduce the index by 1 making last value which was preiously maximum out of scope
}
for (int i = 0; i < n; i++){ //print details
printf("Name: %s\nPrice: %u\n", name[i], price[i]);
}
}