Compilare: user.cpp: In function ‘int sub2(int, int, int*)’: user.cpp:20:10: warning: statement has no effect [-Wunused-value] for(i;i<j;i++) ^ user.cpp: In function ‘int sub1(int, int, int*)’: user.cpp:34:8: warning: statement has no effect [-Wunused-value] for( i;i<=j;i++) sum[i]=vec[i]+sum[i-1]; ^ user.cpp:36:8: warning: statement has no effect [-Wunused-value] for( i;i<=j;i++) ^ user.cpp: In function ‘int main()’: user.cpp:50:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%s", s); ^