Compilare: user.cpp: In function ‘int main()’: user.cpp:15:19: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[260]’ [-Wformat=] scanf("%s",&s); ^ user.cpp:18:18: warning: NULL used in arithmetic [-Wpointer-arith] while(s[i]!=NULL){ ^ user.cpp:8:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mxl.in","r",stdin); ^ user.cpp:9:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mxl.out","w",stdout); ^ user.cpp:12:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&k); ^ user.cpp:14:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&l,&c); ^ user.cpp:15:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",&s); ^