1021 B | 1021 chars
#include <iostream>
using namespace std;
int ar[5][2];
bool check = false;
int main() {
for (int y = 0; y < 3; y++) {
cin >> ar[y][0] >> ar[y][1];
}
for(int big = 0; big<3; big++) {
for(int x=0; x<2; x++) {
for(int y=0; y<2; y++) {
for(int z=0; z<2; z++) {
if(ar[big][x] == ar[(big+1)%3][y] + ar[(big+2)%3][z] && ar[(big+1)%3][1-y] == ar[(big+2)%3][1-z]) {
if(ar[big][x] == ar[big][1-x]+ar[(big+1)%3][1-y]) {
cout<<"YES";
return 0;
}
}
if(ar[big][x] == ar[(big+1)%3][y] &&ar[big][x] == ar[(big+2)%3][z]) {
if(ar[big][x] == ar[big][1-x] + ar[(big+1)%3][1-y] + ar[(big+2)%3][1-z]) {
cout<<"YES";
return 0;
}
}
}
}
}
}
cout<<"NO";
}