SMMR-T226: Two Water Tanks

#include <iostream>
#include <queue>
#include <map>
using namespace std;

#define pii pair<int, int>
typedef long long lli;

int a, b, t, q;

lli BFSWater(pii s){
    queue<pii> q;
    map<pii, lli> dist;
    dist[s] = 0;
    q.push(s);
    while(!q.empty()){
        int u1 = q.front().first;
        int u2 = q.front().second;
        pii u = q.front();
        q.pop();
        if(u1 == t || u2 == t){
            return dist[u];
        }
        /// Fill
        if(dist.find({a, u2}) == dist.end()){
            dist[{a, u2}] = dist[u] + 1;
            q.push({a, u2});
        }
        if(dist.find({u1, b}) == dist.end()){
            dist[{u1, b}] = dist[u] + 1;
            q.push({u1, b});
        }
        /// Remove
        if(dist.find({0, u2}) == dist.end()){
            dist[{0, u2}] = dist[u] + 1;
            q.push({0, u2});
        }
        if(dist.find({u1, 0}) == dist.end()){
            dist[{u1, 0}] = dist[u] + 1;
            q.push({u1, 0});
        }
        /// Move 1 to 2
        int tmp = (u1 + u2 >= b) ? b : u1 + u2;
        if(dist.find({u1 - (tmp - u2), tmp}) == dist.end()){
            dist[{u1 - (tmp - u2), tmp}] = dist[u] + 1;
            q.push({u1 - (tmp - u2), tmp});
        }
        /// Move 2 to 1
        int tmp2 = (u1 + u2 >= a) ? a : u1 + u2;
        if(dist.find({tmp2, u2 - (tmp2 - u1)}) == dist.end()){
            dist[{tmp2, u2 - (tmp2 - u1)}] = dist[u] + 1;
            q.push({tmp2, u2 - (tmp2 - u1)});
        }
    }
    return -1;
}

int main(){

    scanf("%d", &q);
    for(int i  = 0; i < q; ++i){
        scanf("%d %d %d", &a, &b, &t);
        cout << BFSWater({0, 0}) << "\n";
    }

    return 0;
}