Compilare: user.cpp: In function ‘int main()’: user.cpp:43:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suma3.in","r",stdin); freopen("suma3.out","w",stdout); ^ user.cpp:43:67: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suma3.in","r",stdin); freopen("suma3.out","w",stdout); ^ user.cpp:44:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&a,&b); ^ user.cpp:46:47: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(j=1;j<=b;j++) scanf("%d",&v[i][j]); ^ user.cpp:62:13: warning: iteration 32u invokes undefined behavior [-Waggressive-loop-optimizations] L[i][0]=q; ^ user.cpp:58:2: note: containing loop for(i=1;i<=100;i++) ^