foo.cc: In function 'int main()':
foo.cc:12:9: error: redeclaration of 'int t'
   12 |     int t=m+1;
      |         ^
foo.cc:9:9: note: 'int t' previously declared here
    9 |     int t=m+1;
      |         ^
foo.cc:11:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |       scanf("%d",&w[i]);
      |       ~~~~~^~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务