writing this algorithm with do while loop [closed] - c++

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Closed 10 years ago.
I am trying to solve USACO trainings, The "Your Ride Is Here" problem can be solved with this algorithm:
#include <iostream>
#include <conio.h>
using namespace std;
int Calculated(char * calc_me);
int main() {
char * comet_name = (char*)calloc(sizeof(char), 7);
if (comet_name == NULL) {return 0;}
char * group_name = (char*)calloc(sizeof(char), 7);
if (group_name == NULL) {free(comet_name); return 0;}
cout << "Enter the name of the comet: ";
cin >> comet_name;
cout << "Enter the name of the group: ";
cin >> group_name;
if ((Calculated(comet_name) % 47) == (Calculated(group_name) % 47)) {
cout << "GO";
}
else {
cout << "STAY";
}
free (group_name);
free (comet_name);
return 0;
}
int Calculated (char * calc_me) {
int i;
int total = 1;
for (i = 0; i < 7; i++) {
if (calc_me[i] == '0') {break;}
total *= calc_me[i] - 64;
}
getch();
return total;
}
Im trying to change the for loop with do-while loop, Here is my code,so I replaced it with do-while, it doesn't work, can anyone mention me which part I am doing it wrong?
#include <iostream>
#include <conio.h>
using namespace std;
int Calculated(char * calc_me);
int main() {
char * comet_name = (char*)calloc(sizeof(char), 7);
if (comet_name == NULL) {return 0;}
char * group_name = (char*)calloc(sizeof(char), 7);
if (group_name == NULL) {free(comet_name); return 0;}
cout << "Enter the name of the comet: ";
cin >> comet_name;
cout << "Enter the name of the group: ";
cin >> group_name;
if ((Calculated(comet_name) % 47) == (Calculated(group_name) % 47)) {
cout << "GO";
}
else {
cout << "STAY";
}
free (group_name);
free (comet_name);
return 0;
}
int Calculated (char * calc_me) {
int i;
int total = 0;
do
{
total *= calc_me[i] - 64;
i += 1;
}while(i < 7);
getch();
return total;
}
this is the sample input :
COMETQ
HVNGAT
GO
ABSTAR
USACO
STAY

Answer 1

if (calc_me[i] == '0') {break;}
should read
if (calc_me[i] == '\0') {break;}
and that condition is missing from your do-while version, along with the initialisation of i.
But the main problem is that you changed the initial value of total from 1 to 0:
int total = 0;
so this line
total *= calc_me[i] - 64;
keeps multiplying zero by the next value.

Answer 2

AH!! found it!!
You have initialized total to 0. So, every multiplication becomes 0 hence your functions always returns 0.
Initialize your total variable to 1 and it should work.

Answer 3

In the code snippet below, you need to initialize i with a value before you can do i += 1. You do it in the for statement in the for-loop, similarly you need to do it for the do-while loop as well.
int i = 0; // initialize to 0
int total = 0;
do
{
total *= calc_me[i] - 64;
i += 1;
}while(i < 7);