misc: add already solved challenges

misc/flag_shop/log.txt

@@ -0,0 +1,50 @@
+Welcome to the flag exchange
+We sell flags
+
+1. Check Account Balance
+
+2. Buy Flags
+
+3. Exit
+
+ Enter a menu selection
+2
+Currently for sale
+1. Defintely not the flag Flag
+2. 1337 Flag
+1
+These knockoff Flags cost 900 each, enter desired quantity
+2147440000
+
+The final cost is: -39283200
+
+Your current balance after transaction: 39284300
+
+Welcome to the flag exchange
+We sell flags
+
+1. Check Account Balance
+
+2. Buy Flags
+
+3. Exit
+
+ Enter a menu selection
+2
+Currently for sale
+1. Defintely not the flag Flag
+2. 1337 Flag
+2
+1337 flags cost 100000 dollars, and we only have 1 in stock
+Enter 1 to buy one1
+YOUR FLAG IS: picoCTF{m0n3y_bag5_9c5fac9b}
+Welcome to the flag exchange
+We sell flags
+
+1. Check Account Balance
+
+2. Buy Flags
+
+3. Exit
+
+ Enter a menu selection

misc/flag_shop/store.c

@@ -0,0 +1,79 @@
+#include <stdio.h>
+#include <stdlib.h>
+int main()
+{
+    setbuf(stdout, NULL);
+    int con;
+    con = 0;
+    int account_balance = 1100;
+    while(con == 0){
+        printf("Welcome to the flag exchange\n");
+        printf("We sell flags\n");
+
+        printf("\n1. Check Account Balance\n");
+        printf("\n2. Buy Flags\n");
+        printf("\n3. Exit\n");
+        int menu;
+        printf("\n Enter a menu selection\n");
+        fflush(stdin);
+        scanf("%d", &menu);
+        if(menu == 1){
+            printf("\n\n\n Balance: %d \n\n\n", account_balance);
+        }
+        else if(menu == 2){
+            printf("Currently for sale\n");
+            printf("1. Defintely not the flag Flag\n");
+            printf("2. 1337 Flag\n");
+            int auction_choice;
+            fflush(stdin);
+            scanf("%d", &auction_choice);
+            if(auction_choice == 1){
+                printf("These knockoff Flags cost 900 each, enter desired quantity\n");
+
+                int number_flags = 0;
+                fflush(stdin);
+                scanf("%d", &number_flags);
+                if(number_flags > 0){
+                    int total_cost = 0;
+                    total_cost = 900*number_flags;
+                    printf("\nThe final cost is: %d\n", total_cost);
+                    if(total_cost <= account_balance){
+                        account_balance = account_balance - total_cost;
+                        printf("\nYour current balance after transaction: %d\n\n", account_balance);
+                    }
+                    else{
+                        printf("Not enough funds to complete purchase\n");
+                    }
+                }
+            }
+            else if(auction_choice == 2){
+                printf("1337 flags cost 100000 dollars, and we only have 1 in stock\n");
+                printf("Enter 1 to buy one");
+                int bid = 0;
+                fflush(stdin);
+                scanf("%d", &bid);
+
+                if(bid == 1){
+
+                    if(account_balance > 100000){
+                        FILE *f = fopen("flag.txt", "r");
+                        if(f == NULL){
+                            printf("flag not found: please run this on the server\n");
+                            exit(0);
+                        }
+                        char buf[64];
+                        fgets(buf, 63, f);
+                        printf("YOUR FLAG IS: %s\n", buf);
+                        }
+                    else{
+                        printf("\nNot enough funds for transaction\n\n\n");
+                    }}
+            }
+        }
+        else{
+            con = 1;
+        }
+
+    }
+    return 0;
+}