Compilare: user.cpp: In function ‘int* invers(int*, int, int)’: user.cpp:26:9: warning: address of local variable ‘x2’ returned [-Wreturn-local-addr] int x2[11]; ^ user.cpp: In function ‘void backtracking(int, int)’: user.cpp:115:9: warning: unused variable ‘jst’ [-Wunused-variable] int jst, l, c, i=1; ^ user.cpp:115:14: warning: unused variable ‘l’ [-Wunused-variable] int jst, l, c, i=1; ^ user.cpp:115:17: warning: unused variable ‘c’ [-Wunused-variable] int jst, l, c, i=1; ^ user.cpp:116:10: warning: unused variable ‘gt’ [-Wunused-variable] bool gt; ^ user.cpp: In function ‘int main()’: user.cpp:156:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &n, &k); ^