C++ Programming Question

[Saint Nick]

I compile my program, and I get these errors:

program19.cpp: In function `void generateSieve(bool*, int)':
program19.cpp:63: call of overloaded `sqrt(int)' is ambiguous
/usr/include/bits/mathcalls.h:157: candidates are: double sqrt(double)
/usr/include/c++/3.2.2/cmath:465: long double std::sqrt(long
double)
/usr/include/c++/3.2.2/cmath:461: float std::sqrt(float)


Here is the code involved:

 

[neit]

it looks like in your outer for loop you are taking the square root of an int, and it can't decide whether to cast it as a float, doublt, or a long double. plus, you are comparing the output of it (a floating point number) with an int, which you should becareful about.

here's a tip to help, since you comparison is against a fixed number (sqrt(sievesize-1)), move that to before the loop starts, that way you aren't calculating it repeatedly.

hope that helps

 

[Saint Nick]

I got the program to compile. However, now it is giving this error, and my teacher's submition program is saying it won't be graded unless this error is removed.

program19.cpp: In function `void generateSieve(bool*, int)':
program19.cpp:65: warning: statement with no effect

Here is the new code I made:

 

[notfred]

You're getting that warning (it's not an error) because the line:

static_cast<int>(temp);

does absolutely nothing.

 

[itachi]

the error was with the cast..
static_cast<int>(temp);
is a statement with no effect. the variable temp was declared as a double, you can't change that but u can cast it to another int variable.