Any wrong with my for loop?

[nickyeng]

It compiled no errors, but got warning.

warning : comparison between signed and unsigned integer expression.

how am i going to eliminate the warning part?
here is my code:

string f(string str){
    transform(str.begin(), str.end(), str.begin(), ptr_fun(::tolower));
 
    for(int j=0; j< str.length(); j++)
    {
        if(ispunct(str[j])){
        str.erase(j,1);
        break;
        }
    }
    return str;
}
 

thanks in advance.

[smartway]

In your program j is int that is nothing but the signed int and length funtion returns unsigned int. To avoid this warning you have to make both of same type.
If you declare j as unsigned int then the warning will not come or you will have to do cast conversion of return type of length function.

[snixten]

Instead of:

for(int j=0; j < str.length(); j++)

write:

for(int j=0; j < (int) str.length(); j++)