Submission #3191106

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Source Code Expand

#include<bits/stdc++.h>
#define ll long long
#define db double
#define lowbit(p) (p&(-p))
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define A first
#define B second
using namespace std;
void read(int &x){
	x=0; char c=getchar(); int p=1;
	for (;c<48;c=getchar())if (c=='-')p=-1;
	for (;c>47;c=getchar())x=(x<<1)+(x<<3)+(c^48);
	x*=p;
}
void read(ll &x){
	x=0; char c=getchar(); int p=1;
	for (;c<48;c=getchar())if (c=='-')p=-1;
	for (;c>47;c=getchar())x=(x<<1)+(x<<3)+(c^48);
	x*=p;
}
void Min(int &x,int y){
	if (x>y)x=y;
}
void Max(int &x,int y){
	if (x<y)x=y;
}
void Min(ll &x,ll y){
	if (x>y)x=y;
}
void Max(ll &x,ll y){
	if (x<y)x=y;
}
/*
## 题意:
有一个(n*m)的矩阵,要求每次交换两行,或者两列.使得矩阵对称
a[i][j]=a[n-i+1][m-j+1]

单独考虑行和列?
12!
*/
int n,m,cnt[26],a[50][50];
char s[50];
bool chk1(int x,int y){
	int i;
	for (i=0;i<26;i++)cnt[i]=0;
	for (i=1;i<=m;i++){
		cnt[a[x][i]]++;
		cnt[a[y][i]]--;
	}
	for (i=0;i<26;i++)if (cnt[i])return 0;
	return 1;
}
bool chk2(int x,int y){
	int i;
	for (i=0;i<26;i++)cnt[i]=0;
	for (i=1;i<=n;i++){
		cnt[a[i][x]]++;
		cnt[a[i][y]]--;
	}
	for (i=0;i<26;i++)if (cnt[i])return 0;
	return 1;
}
void swa1(int x,int y){
	for (int i=1;i<=m;i++){
		swap(a[x][i],a[y][i]);
	}
}
void swa2(int x,int y){
	for (int i=1;i<=n;i++){
		swap(a[i][x],a[i][y]);
	}
}
void chk(){
	int i,j;
	for (i=1;i<=n;i++){
		for (j=1;j<=m;j++){
			if (a[i][j]!=a[n-i+1][m-j+1]){
				return ;
			}
		}
	}	
	printf("YES\n");
	exit(0);
}
void dfs2(int x){
	if (x>=m-x+1){
//		printf("?\n");
		chk();
		return ;
	}
	for (int i=x+1;i<=m-x+1;i++){
		if (chk2(x,i)){
			swa2(m-x+1,i);
			dfs2(x+1);
			swa2(m-x+1,i);
		}
	}
}
void dfs1(int x){
//	printf("x=%d\n",x);
	if (x>=n-x+1){
		dfs2(1);
		return ;
	}
	for (int i=x+1;i<=n-x+1;i++){
		if (chk1(x,i)){
			swa1(n-x+1,i);
			dfs1(x+1);
			swa1(n-x+1,i);
		}
	}
}
int main(){
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
//	freopen("1.in","r",stdin);
	read(n); read(m);
	int i,j;
	for (i=1;i<=n;i++){
		scanf("%s",s+1);
		for (j=1;j<=m;j++){
			a[i][j]=s[j]-'a';
		}
	}/*
	for (i=1;i<=n;i++){
		for (j=1;j<=n;j++)can1[i][j]=chk1(i,j);
	}
	for (i=1;i<=m;i++){
		for (j=1;j<=m;j++)can2[i][j]=chk2(i,j);
	}*/
	for (i=1;i<=n;i++){
		swa1(i,n/2);
		for (j=1;j<=m;j++){
			swa2(j,m/2);
			dfs1(1);
			swa2(j,m/2);
		}
		swa1(i,n/2);
	}
	printf("NO\n");
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:122:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%s",s+1);
                  ^

Judge Result