merchant.cpp: In function 'int main()':
merchant.cpp:35:8: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
35 | mid=r+l>>1;
| ~^~
merchant.cpp: In function 'void usaco(std::string)':
merchant.cpp:5:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:5:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp: In function 'int main()':
merchant.cpp:27:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
27 | scanf("%d %d %d",&n,&m,&k);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~
merchant.cpp:28:49: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
28 | for(int i=1;i<=n;i++)for(int j=1;j<=k;j++)scanf("%d %d",&b[i][j],&s[i][j]);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:31:28: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
31 | for(int i=1;i<=m;i++)scanf("%d %d",&u,&v),scanf("%lld",&dist[u][v]);
| ~~~~~^~~~~~~~~~~~~~~
merchant.cpp:31:49: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
31 | for(int i=1;i<=m;i++)scanf("%d %d",&u,&v),scanf("%lld",&dist[u][v]);
| ~~~~~^~~~~~~~~~~~~~~~~~~~