Compilare: user.cpp: In function ‘int main()’: user.cpp:16:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=2;i<=strlen(a);i++) { ^ user.cpp:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(b);i++) { ^ user.cpp:25:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(q==strlen(a)) { ^ user.cpp:13:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%s%s",a,b); ^