Compilare: user.c: In function ‘main’: user.c:5:5: warning: implicit declaration of function ‘strlen’ [-Wimplicit-function-declaration] freopen("paritate.in","r",stdin),freopen("paritate.out","w",stdout),scanf("%s\n",s),k=strlen(s); ^ user.c:5:91: warning: incompatible implicit declaration of built-in function ‘strlen’ [enabled by default] freopen("paritate.in","r",stdin),freopen("paritate.out","w",stdout),scanf("%s\n",s),k=strlen(s); ^ user.c:5:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("paritate.in","r",stdin),freopen("paritate.out","w",stdout),scanf("%s\n",s),k=strlen(s); ^ user.c:5:45: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("paritate.in","r",stdin),freopen("paritate.out","w",stdout),scanf("%s\n",s),k=strlen(s); ^ user.c:5:78: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("paritate.in","r",stdin),freopen("paritate.out","w",stdout),scanf("%s\n",s),k=strlen(s); ^