help please c++

[abdul12]

how to find a lowest grade in programing using the c++.
example: {65,89,100,76,80}.
#include<iostream>
using std::cout;
using std::endl;
int main()
{
float grade=0;
int sum=0
int lab[]={};
int numElems=sizeof(lab)/sizeof(int);
for (int ndx=0; ndx<numElems;ndx++)sum=lab[ndx];
grade=static_cast<float>(sum)/numElems;
cout<<"your grade:"<<grade<<endl;
return EXUT_SUCCESS; }................please refer to this method. thanks

[dhayden]

sum = lab[ndx] should be sum+= lab[ndx].