Compilare: main.cpp:2:26: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^ main.cpp: In function 'int main()': main.cpp:2:69: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^ main.cpp:2:99: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^ main.cpp:2:114: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^ main.cpp:2:141: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^ main.cpp:2:182: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;main(){int x,n,s,i,a;freopen("nim.in","r",stdin);freopen("nim.out","w",stdout);scanf("%d",&x);while(x--){scanf("%d", &n);for(i=1,s=0;i<=n;i++)scanf("%d",&a),s^=a;printf("%s\n",(s==0)?"NU":"DA");}return 0;} ^