foo.c:2:1: error: unknown type name 'using'
    2 | using namespace std;
      | ^~~~~
foo.c:2:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'std'
    2 | using namespace std;
      |                 ^~~
foo.c:5:7: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
    5 | vector<int>a[max];
      |       ^
foo.c:7:1: error: unknown type name 'bool'
    7 | bool ok(int x)
      | ^~~~
foo.c: In function 'ok':
foo.c:9:8: error: 'a' undeclared (first use in this function)
    9 |     if(a[x].size()==0)return 0;
      |        ^
foo.c:9:8: note: each undeclared identifier is reported only once for each function it appears in
foo.c:10:5: error: unknown type name 'bool'
   10 |     bool ret=0;
      |     ^~~~
foo.c:13:14: error: called object is not a function or function pointer
   13 |         now= max(0, now -(a[x][i]-a[x][i-1]-1) );
      |              ^~~
foo.c:18:10: error: called object is not a function or function pointer
   18 |     now= max(0, now -(t-a[x][a[x].size()-1]));
      |          ^~~
foo.c: In function 'main':
foo.c:28:9: error: 'a' undeclared (first use in this function)
   28 |         a[id].push_back(ts);
      |         ^
foo.c:33:19: error: 'true' undeclared (first use in this function)
   33 |         if(ok(i)==true)ans++;
      |                   ^~~~
foo.c:23:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   23 |     scanf("%d%d%d",&n,&m,&t);
      |     ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:27:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |         scanf("%d%d",&ts,&id);
      |         ^~~~~~~~~~~~~~~~~~~~~

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