Compilare: user.cpp: In function ‘int main()’: user.cpp:13:28: warning: format ‘%c’ expects argument of type ‘char*’, but argument 4 has type ‘int*’ [-Wformat=] scanf("%d%d%c",&n,&m,&c); ^ user.cpp:30:9: warning: ‘char* gets(char*)’ is deprecated [-Wdeprecated-declarations] gets(sir); ^~~~ In file included from /usr/include/c++/6/cstdio:42:0, from user.cpp:1: /usr/include/stdio.h:638:14: note: declared here extern char *gets (char *__s) __wur __attribute_deprecated__; ^~~~ user.cpp:30:17: warning: ‘char* gets(char*)’ is deprecated [-Wdeprecated-declarations] gets(sir); ^ In file included from /usr/include/c++/6/cstdio:42:0, from user.cpp:1: /usr/include/stdio.h:638:14: note: declared here extern char *gets (char *__s) __wur __attribute_deprecated__; ^~~~ user.cpp:10:24: warning: unused variable ‘y’ [-Wunused-variable] int n,m,i,inc,sf,x,y,xi,yi,xf,yf,l,c,j,pozi,pozj; ^ user.cpp:11:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.in","r",stdin); ^ user.cpp:12:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.out","w",stdout); ^ user.cpp:13:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%c",&n,&m,&c); ^ user.cpp:30:18: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(sir); ^ user.cpp:80:14: warning: ‘yf’ may be used uninitialized in this function [-Wmaybe-uninitialized] b[xf][yf]=1; ~~~~~~~~~^~ user.cpp:80:14: warning: ‘xf’ may be used uninitialized in this function [-Wmaybe-uninitialized] user.cpp:60:14: warning: ‘yi’ may be used uninitialized in this function [-Wmaybe-uninitialized] a[xi][yi]=1; ~~~~~~~~~^~ user.cpp:60:14: warning: ‘xi’ may be used uninitialized in this function [-Wmaybe-uninitialized] /tmp/ccktWE3A.o: In function `main': user.cpp:(.text.startup+0x139): warning: the `gets' function is dangerous and should not be used.