Compilare: user.c: In function ‘main’: user.c:6:24: warning: unused variable ‘c’ [-Wunused-variable] char v[100001] = {0}, c; ^ user.c:5:22: warning: variable ‘length’ set but not used [-Wunused-but-set-variable] int n, k, i = 1, j, length, m = 0; ^ user.c:5:19: warning: unused variable ‘j’ [-Wunused-variable] int n, k, i = 1, j, length, m = 0; ^ user.c:11:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d ",&n,&k); ^ user.c:19:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%c",&v[m]); ^