标签:sea highlight strong http efi icpc test uil tin
题目链接 2013杭州区域赛
Problem A
Problem B
这题我用的是SPFA+ mask dp
首先跑5次SPFA:
1次是求出每个起点和其他所有点的最短距离
4次是求出每个输入的点和其他所有点的最短距离
然后就是dp
设dp[mask][i]为,mask状态下,以i为终点的最优方案
然后做一遍状压DP即可。
#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for (int i(a); i <= (b); ++i)
#define dec(i, a, b) for (int i(a); i >= (b); --i)
const int N = 103;
const int M = 1e4 + 10;
const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, 1, 0, -1};
bool inqueue[M], fl;
int c[N][N], f[6][6], a[M], d[M], dp[101][6];
char s[N][N];
int cnt, n, m, k;
vector <int> v[M];
inline void addedge(int x, int y){
v[x].push_back(y);
v[y].push_back(x);
}
void SPFA(int s){
memset(inqueue, false, sizeof inqueue);
rep(i, 1, cnt) d[i] = 1 << 29;
d[s] = 0;
queue <int> q;
q.push(s);
while (!q.empty()){
int x = q.front();
q.pop();
inqueue[x] = false;
for (auto u : v[x]){
if (d[u] > d[x] + 1){
d[u] = d[x] + 1;
if (!inqueue[u]){
inqueue[u] = true;
q.push(u);
}
}
}
}
}
int main(){
while (~scanf("%d%d", &n, &m), n + m){
rep(i, 1, n) scanf("%s", s[i] + 1);
cnt = 0;
rep(i, 1, n) rep(j, 1, m) c[i][j] = ++cnt;
scanf("%d", &k);
rep(i, 1, n) rep(j, 1, m) if (s[i][j] == ‘@‘){
a[k] = c[i][j];
s[i][j] = ‘.‘;
break;
}
rep(i, 0, k - 1){
int x, y;
scanf("%d%d", &x, &y);
a[i] = c[x][y];
}
rep(i, 0, n * m + 1) v[i].clear();
rep(i, 1, n){
rep(j, 1, m) if (s[i][j] == ‘.‘){
rep(k, 0, 3){
int x = i + dx[k], y = j + dy[k];
if (s[x][y] == ‘.‘){
addedge(c[i][j], c[x][y]);
}
}
}
}
SPFA(a[k]);
rep(i, 0, k) rep(j, 0, k) f[i][j] = 1 << 29;
rep(i, 0, k){
SPFA(a[i]);
rep(j, 0, k) if (i == j) f[i][j] = 0;
else f[i][j] = d[a[j]];
}
rep(i, 0, 53) rep(j, 0, 5) dp[i][j] = 1 << 29;
rep(i, 0, k - 1) dp[1 << i][i] = f[i][k];
rep(i, 1, ((1 << k) - 1)){
if (__builtin_popcount(i) != 1){
rep(j, 0, k - 1) if ((i >> j) & 1){
rep(l, 0, k - 1) if (((i >> l) & 1) && (j != l)){
dp[i][j] = min(dp[i][j], dp[i ^ (1 << j)][l] + f[j][l]);
}
}
}
}
int ans = 1 << 30;
rep(i, 0, k - 1) ans = min(ans, dp[(1 << k) - 1][i]);
printf("%d\n", ans < 1e6 ? ans : -1);
}
return 0;
}
Problem C
跟着题意模拟一遍
关键是那个旋转要一次性写对
#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for (int i(a); i <= (b); ++i)
#define dec(i, a, b) for (int i(a); i >= (b); --i)
const int N = 41;
int a[N][N], b[N][N];
int n;
int ans;
void solve(){
int c[N][N]; memset(c, 0, sizeof c);
rep(i, 1, n) rep(j, 1, n) c[i][j] = a[j][n - i + 1];
rep(i, 1, n) rep(j, 1, n) a[i][j] = c[i][j];
}
int main(){
while (~scanf("%d", &n), n){
rep(i, 1, n) rep(j, 1, n) scanf("%d", &a[i][j]);
rep(i, 1, n) rep(j, 1, n) scanf("%d", &b[i][j]);
ans = 0;
rep(p, 1, 4){
solve();
int now = 0;
rep(i, 1, n) rep(j, 1, n) if (a[i][j] == b[i][j]) ++now;
ans = max(ans, now);
}
printf("%d\n", ans);
}
return 0;
}
Problem D
Problem E
Problem F
Problem G
Problem H
Problem I
Problem J
Problem K
标签:sea highlight strong http efi icpc test uil tin
原文地址:http://www.cnblogs.com/cxhscst2/p/7624709.html