CF 191 div2 (二)
int64 ans = 0;
__int64 q = 0;
for(int i=0; i
if(str[i] == '0' || str[i] == '5') {
q = (q + model(2,i,mod)) % mod;
}
}
ans = model(2,len*k,mod) % mod - 1;
ans = (ans*model(model(2,len,mod) -1,mod - 2,mod)) % mod;
ans = (q*ans) % mod;
printf("%I64d\n",ans);
return 0;
}
D.Block Tower
带有YY的爆搜，满足让一个联通块内只有一个blue房子其他都是red房子
[cpp]
char map[MAX][MAX];
int vis[MAX][MAX];
struct node {
int x,y;
char dir;
} p[1000005];
int dirx[4] = {1,-1,0,0};
int diry[4] = {0,0,1,-1};
int ans = 0 ,i,j;
void dfs(int x,int y) {
p[ans].dir = 'B';
p[ans].x = x;
p[ans].y = y;
ans++;
vis[x][y] = 1;
for(int k=0; k<4; k++) {
int xx = x + dirx[k];
int yy = y + diry[k];
if(!vis[xx][yy] && map[xx][yy] == '.')
dfs(xx,yy);
}
if(x != i || j != y){
p[ans].dir = 'D';
p[ans].x = x;
p[ans].y = y;
ans++;
p[ans].dir = 'R';
p[ans].x =x;
p[ans].y = y;
ans++;
}
}
int main() {
int n,m;
scanf("%d%d",&n,&m);
for(i=0; i
scanf("%s",map[i]);
}
for(i=0; i
for(j=0; j
if(map[i][j] == '.' && !vis[i][j]) {
dfs(i,j);
}
}
}
printf("%d\n",ans);
for(i=0; i
printf("%c %d %d\n",p[i].dir,p[i].x+1,p[i].y+1);
}
return 0;
}
char map[MAX][MAX];
int vis[MAX][MAX];
struct node {
int x,y;
char dir;
} p[1000005];
int dirx[4] = {1,-1,0,0};
int diry[4] = {0,0,1,-1};
int ans = 0 ,i,j;
void dfs(int x,int y) {
p[ans].dir = 'B';
p[ans].x = x;
p[ans].y = y;
ans++;
vis[x][y] = 1;
for(int k=0; k<4; k++) {
int xx = x + dirx[k];
int yy = y + diry[k];
if(!vis[xx][yy] && map[xx][yy] == '.')
dfs(xx,yy);
}
if(x != i || j != y){
p[ans].dir = 'D';
p[ans].x = x;
p[ans].y = y;
ans++;
p[ans].dir = 'R';
p[ans].x =x;
p[ans].y = y;
ans++;
}
}
int main() {
int n,m;
scanf("%d%d",&n,&m);