/in/lab4.c: In function 'pf':
/in/lab4.c:288:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while(i<=strlen(str)){
            ^~
/in/lab4.c: In function 'var':
/in/lab4.c:259:8: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]
     if (n!=1){
        ^