Compilare: user.cpp: In function ‘void shellsort(int (*)[4], int)’: user.cpp:8:9: warning: unused variable ‘k’ [-Wunused-variable] int j,i,k,m,mid; ^ user.cpp: In function ‘int main()’: user.cpp:37:23: warning: unused variable ‘b’ [-Wunused-variable] int n,a[50000][4],b[50000]; ^ user.cpp:38:14: warning: unused variable ‘t’ [-Wunused-variable] interval t[50000]; ^ user.cpp:42:8: warning: unused variable ‘mn’ [-Wunused-variable] int mn,man,k,mn2; ^ user.cpp:42:11: warning: unused variable ‘man’ [-Wunused-variable] int mn,man,k,mn2; ^ user.cpp:42:15: warning: unused variable ‘k’ [-Wunused-variable] int mn,man,k,mn2; ^ user.cpp:42:17: warning: unused variable ‘mn2’ [-Wunused-variable] int mn,man,k,mn2; ^ user.cpp:41:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(pFile,"%d",&n); ^ user.cpp:47:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(pFile,"%d",&a[i][1]); ^ user.cpp:48:39: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(pFile,"%d",&a[i][2]); ^