Compilare: user.cpp: In function ‘int main()’: user.cpp:37:5: warning: unused variable ‘n’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:7: warning: unused variable ‘t1’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:10: warning: unused variable ‘t2’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:13: warning: unused variable ‘s1’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:16: warning: unused variable ‘s2’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:19: warning: unused variable ‘s3’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:22: warning: unused variable ‘s4’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:25: warning: unused variable ‘r1’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:28: warning: unused variable ‘r2’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:31: warning: unused variable ‘r3’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:34: warning: unused variable ‘r4’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:37:37: warning: unused variable ‘cate’ [-Wunused-variable] int n,t1,t2,s1,s2,s3,s4,r1,r2,r3,r4,cate=0,z=0,q=0; ^ user.cpp:34:28: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ai.in","r",stdin); ^ user.cpp:35:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ai.out","w",stdout); ^ user.cpp:42:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int lin,col;scanf ("%d%d",&lin,&col); ^