#include "fish.h"
#include <vector>
using namespace std;
#define ll long long
long long max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W) {
ll rightsum=0, leftsum=0;;
vector<int> left(N, 0), right(N, 0); // v[0] = bottom, ...
for(int i=0; i<M; i++){
if(X[i]==0){
left[Y[i]] = W[i];
leftsum += W[i];
} else{
right[Y[i]] = W[i];
rightsum += W[i];
}
}
if(N==2) return max(leftsum,rightsum);
// we could place a pier on the right (x=2 / third column)...
ll cur_val = rightsum;
ll answer = cur_val;
for(int y=0; y<N; y++){
// what if we built a pier on the 2nd column which has height y+1?
cur_val -= right[y];
cur_val += left[y];
answer = max(answer, cur_val);
}
return answer;
}
