lang.cpp: In function 'int main()':
lang.cpp:21:11: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
freopen("grader.in.1", "r", stdin);
~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
lang.cpp:29:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
for (i=0;i<N;i++) scanf("%d,",&uni[i]);
~~~~~^~~~~~~~~~~~~~~
lang.cpp:30:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%*[^\n]");
~~~~~^~~~~~~~~~~
/tmp/ccQDeTPg.o: In function `language(int)':
grader.c:(.text+0x0): multiple definition of `language(int)'
/tmp/cc2pRtk9.o:lang.cpp:(.text+0x0): first defined here
/tmp/ccQDeTPg.o: In function `main':
grader.c:(.text.startup+0x0): multiple definition of `main'
/tmp/cc2pRtk9.o:lang.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status