Compilare: user.c: In function ‘main’: user.c:5:22: warning: unused variable ‘c’ [-Wunused-variable] char a,b[20][20],c; ^ user.c:10:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:15:19: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:19:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:21:19: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:24:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:25:19: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:27:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:30:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:35:27: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:37:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:48:27: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:52:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:62:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:73:19: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:80:27: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f_in,"%c",&a); ^ user.c:83:23: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]