Compilare: main.cpp: In function 'int is_prime(int)': main.cpp:9:16: warning: suggest parentheses around '&&' within '||' [-Wparentheses] if(x<2||x>2&&x%2==0)return 0; ~~~^~~~~~~~ main.cpp: In function 'int main()': main.cpp:37:31: warning: unused variable 'nmatches' [-Wunused-variable] int h1=0,h2=0,hs1=0,hs2=0,nmatches=0,pow1=1,pow2=1,np=0; ^~~~~~~~ main.cpp:25:23: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(patt,lmax,f); ^ main.cpp:26:20: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(s,lmax,f); ^