Please give me a solution...why gets compilation error in online judge..????

Question

show the message ""Can\u0027t compile file: program.c:1:19: fatal error: iostream: No such file or directory compilation terminated. " when submit the programme...

## programme..##
#include<iostream>
using namespace std;
#include<map>
map<string,int>mp,nmp;
string name[1002];
int score[1002];

int main()
{
int n,s;
string winner_name;
cin>>n;
//This section is for first map.
for(int i=0;i<n;i++)
{
cin>>winner_name>>s;
name[i] =winner_name;
score[i] = s;
if(mp.find(winner_name)!=mp.end())
{
mp[winner_name]+=s;
}
else{
mp[winner_name] = s;
}

}
//This section is for select maximum points
long long maxi=-1001;
for(map<string,int>::iterator it=mp.begin();it!=mp.end();++it)
{
if(maxi<it->second)
{
maxi=it->second;
}
}
for(int i=0;i<n;i++)
{
if(nmp.find(name[i])!=nmp.end())
{
nmp[name[i]]+=score[i];
}
else
{
nmp[name[i]]=score[i];
}
if(maxi<=nmp[name[i]] and mp[name[i]]==maxi)
{
cout<<name[i]<<endl;
return 0;
}
}

return 0;
}