code help!

can someone please help with describing what the output of this program would be?^

Code:

---

main()
        {
                for (int i = 0; i < 8; i++)
                        if (i%2 == 0) cout << i +1 << “\t”;
                          else if (i%3) == 0) cout << i * i  << “\t”;
                          else if (i%5 == 0) cout << 2*i – 1 << “\t”;
                          else cout << i << “\t”;
        }

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Surely you have a problem if the number divides by 3 and 2 like 6

if int i/2 gives no remainder then it will output i+1
else if i/3 gives no remainder then the output will be i^2
else if i/5 gives no remainder the output will be 2*i - 1
otherwise the output will be i

well, if you #include <iostream>, use namespace std, and put an int before main, you get... nothing.

Code:

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jshao@MCP ~/Programming/C++/test $ g++ test.cpp -Wall -W -ansi -pedantic -o test.exe && ./test.exe
test.cpp: In function `int main()':
test.cpp:9: error: syntax error before `==' token
test.cpp:10: error: syntax error before `else'

---

that for loop is constructed wrong, and your parenthesis are messed up.

after fixing the loop and parenthesis and making it more readable, and adding comments, it becomes more clear:

Code:

---

#include <iostream>

using namespace std;

int main()
{
        for (int i=0;i<8;i++)
        {
                if (i%2==0)                //if the remainder of i/2 is zero
                {
                        cout<<i+1<<'\t';        //output i+1 and a tab
                }
                else if (i%3 == 0)        //if the remainder of i/3 is zero
                {
                        cout<<i*i<<'\t';        //output i*i and a tab
                }
                else if (i%5 == 0)        //if the remainder of i/5  is zero
                {
                        cout<<2*i-1<<'\t';        //output (2*i)-1 and a tab
                }
                else                        //otherwise
                {
                        cout<<i<<'\t';                //just output i
                }
        }
}

---

and now when you compile and run that, you get:

Code:

---

jshao@MCP ~/Programming/C++/test $ g++ test.cpp -Wall -W -ansi -pedantic -o test.exe && ./test.exe
1      1      3      9      5      9      7      7

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basically, if i is an even number (in this case, 2,4,6,8), it'll add one to i, and if it's a multiple of three (in this case, only when i is 3), it'll square the nubmer, and when it's a multiple of 5 (in this case only when it's 5), it'll multiply i by 2 and subtract 1. That leaves you with 1 and 7, which just gets printed for what it is.