Compilare: user.cpp: In function ‘int main()’: user.cpp:41:21: warning: NULL used in arithmetic [-Wpointer-arith] while(s[0]!=NULL) ^ user.cpp:44:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[j2]>='0'&&s[j2]<='9'&&j2<strlen(s)) j2++; ^ user.cpp:49:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[j3]!='+'&&j3<strlen(s)) j3++; ^ user.cpp:38:13: warning: unused variable ‘j’ [-Wunused-variable] int j=0,Sum=0; ^