[유니온 파인드]11월 29일

[union find]1129/1043.cpp

@@ -0,0 +1,78 @@
+//
+// Created by LG on 2021-11-27.
+//
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+vector<int> parent;
+vector<bool> truth;
+
+int findParent(int node){
+    if(parent[node] < 0)
+        return node;
+    return parent[node] = findParent(parent[node]);
+}
+
+void unionInput(int x, int y){
+    int xp = findParent(x);
+    int yp = findParent(y);
+
+    if(xp == yp)
+        return;
+    if(truth[xp] || truth[yp])
+        truth[xp] = truth[yp] = true;
+    if(parent[xp] < parent[yp]){
+        parent[xp] += parent[yp];
+        parent[yp] = xp;
+    }
+    else{
+        parent[yp] += parent[xp];
+        parent[xp] = yp;
+    }
+}
+
+int main(){
+    int n, m, k;
+    cin >> n >> m >> k;
+    int cnt = m;
+    parent.assign(n+1, -1);
+    truth.assign(n+1, false);
+    vector<vector<int>> party(m, vector<int>());
+
+    for(int i=0; i<k; i++){
+        int p;
+        cin >> p;
+        truth[p] = true;
+    }
+
+    for(int i=0; i<m; i++){
+        int t;
+        cin >> t;
+        party[i].assign(t, 0);
+
+        for(int j=0; j<t; j++){
+            int p;
+            cin >> p;
+            party[i][j] = p;
+        }
+
+        for(int j=0; j<t; j++){
+            for(int l=j+1; l<t; l++)
+                unionInput(party[i][j], party[i][l]);
+        }
+    }
+
+    for(int i=0; i<m; i++){
+        for(int j=0; j<party[i].size(); j++){
+            if(truth[findParent(party[i][j])]){
+                cnt--;
+                break;
+            }
+        }
+    }
+
+    cout << cnt;
+    return 0;
+}

[union find]1129/18111.cpp

@@ -0,0 +1,58 @@
+//
+// Created by LG on 2021-11-28.
+//
+#include <iostream>
+#include <vector>
+#include <climits>
+
+using namespace std;
+
+const int MAX = INT_MAX;
+
+int main(){
+    int n, m, b;
+    cin >> n >> m >> b;
+
+    vector<vector<int>> height(n, vector<int>(m, 0));
+    int min_h = 256;
+    int max_h = 0;
+    for(int i=0; i<n; i++){
+        for(int j=0; j<m; j++) {
+            cin >> height[i][j];
+            if(height[i][j] < min_h)
+                min_h = height[i][j];
+            if(height[i][j] > max_h)
+                max_h = height[i][j];
+        }
+    }
+
+    int ans_time = MAX;
+    int ans_h;
+    while(min_h <= max_h){
+        int time = 0;
+        int b_temp = b;
+        for(int i=0; i<n; i++){
+            for(int j=0; j<m; j++){
+                if(height[i][j] > min_h){
+                    int diff = height[i][j] - min_h;
+                    time += 2*diff;
+                    b_temp += diff;
+                }
+                else if(height[i][j] < min_h){
+                    int diff = min_h - height[i][j];
+                    time += diff;
+                    b_temp -= diff;
+                }
+            }
+        }
+
+        if(b_temp >= 0 && time <= ans_time) {
+            ans_time = time;
+            ans_h = min_h;
+        }
+        min_h++;
+    }
+
+    cout << ans_time << ' ' << ans_h;
+    return 0;
+}

[union find]1129/1976.cpp

@@ -0,0 +1,74 @@
+//
+// Created by LG on 2021-11-28.
+//
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+vector<int> parent;
+
+int findParent(int node){
+    if(parent[node] < 0)
+        return node;
+    else
+        return parent[node] = findParent(parent[node]);
+}
+
+void unionInput(int x, int y){
+    int xp = findParent(x);
+    int yp = findParent(y);
+
+    if(xp == yp)
+        return;
+    if(parent[xp] < parent[yp]){
+        parent[xp] += parent[yp];
+        parent[yp] = xp;
+    }
+    else{
+        parent[yp] +=  parent[xp];
+        parent[xp] = yp;
+    }
+
+}
+
+bool result(int m, vector<int> route){
+    for(int i=0; i<m-1; i++){
+        int p1 = findParent(route[i]);
+        int p2 = findParent(route[i+1]);
+        if(p1 != p2)
+            return false;
+    }
+    return true;
+}
+
+int main(){
+    int n, m;
+    cin >> n >> m;
+    parent.assign(n+1, -1);
+    vector<vector<int>> cities(n+1, vector<int>(n+1));
+    vector<int> route(m, 0);
+    for(int i=1; i<=n; i++){
+        for(int j=1; j<=n; j++){
+            cin >> cities[i][j];
+        }
+    }
+
+    for(int i=0; i<m; i++){
+        cin >> route[i];
+    }
+
+    for(int i=1; i<=n; i++){
+        for(int j=i+1; j<=n; j++){
+            if(cities[i][j]==1)
+                unionInput(i, j);
+        }
+    }
+
+    if(result(m, route))
+        cout << "YES";
+    else
+        cout << "NO";
+
+    return 0;
+}

[union find]1129/20040.cpp

@@ -0,0 +1,48 @@
+//
+// Created by LG on 2021-11-27.
+//
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+vector<int> parent;
+
+int findParent(int node){
+    if(parent[node] < 0)
+        return node;
+    return parent[node] = findParent(parent[node]);
+}
+
+bool unionInput(int x, int y){
+    int xp = findParent(x);
+    int yp = findParent(y);
+
+    if(xp == yp){
+        return true;
+    }
+    if(parent[xp] < parent[yp]){
+        parent[xp] += parent[yp];
+        parent[yp] = xp;
+    }
+    else{
+        parent[yp] += parent[xp];
+        parent[xp] = yp;
+    }
+    return false;
+}
+
+int main(){
+    int n, m, a, b;
+    cin >> n >> m;
+    parent.assign(n, -1);
+    for(int i=0; i<m; i++){
+        cin >> a >> b;
+        if(unionInput(a, b)) {
+            cout << i+1;
+            return 0;
+        }
+    }
+    cout << '0';
+    return 0;
+}