1 #include "iostream"
 2 #include "cstdio"
 3 #include "cstring"
 4 #include "string"
 5 using namespace std;
 6 const int maxn=1e5+10;
 7 long long a[maxn],x;
 8 int n;
 9 int main()
10 {
11     cin>>n>>x;
12     for(int i=0;i<n;i++)
13     scanf("%lld",&a[i]);
14     long long ans=0;
15     for(int i=1;i<n;i++){
16         if(a[i]+a[i-1]>x){
17             long long num=a[i]+a[i-1]-x;
18             if(a[i]>=num){
19                 a[i]-=num;
20                 ans+=num;
21             }else{
22                 long long tt=num-a[i];
23                 a[i-1]-=tt;
24                 a[i]=0;
25                 ans+=num;
26             }
27         }
28     }
29     cout<<ans<<endl;
30     return 0;
31 }

 1 #include "iostream"
 2 #include "cstdio"
 3 #include "cstring"
 4 #include "queue"
 5 using namespace std;
 6 const int maxn=1100;
 7 int vis[maxn][maxn][2];
 8 int h,w,d,r;
 9 char s[maxn][maxn];
10 int dx[]={1,-1,0,0};
11 int dy[]={0,0,1,-1};
12 struct Node{
13     int x,y,flag,step;
14 };
15 int bfs(){
16     Node t;
17     t.x=1,t.y=1,t.flag=0,t.step=0;
18     queue<Node>p;
19     vis[t.x][t.y][t.flag]=1;
20     p.push(t);
21     while(!p.empty()){
22         Node e,f;
23         e=p.front(); p.pop();
24         if((vis[e.x][e.y][0]||vis[e.x][e.y][1])&&(e.x==h&&e.y==w))
25         return e.step;
26         for(int i=0;i<4;i++){
27             int x=e.x+dx[i],y=e.y+dy[i];
28             if(x<=0||x>h||y<=0||y>w)  continue;
29             if(s[x][y]==‘#‘||vis[x][y][e.flag])  continue;
30             vis[x][y][e.flag]=1;
31             f.x=x,f.y=y,f.flag=e.flag,f.step=e.step+1;
32             p.push(f);
33         }
34         if(e.flag==0){
35             int xx=e.x+d,yy=e.y+r;
36             if(xx<=0||xx>h||yy<=0||yy>w) continue;
37             if(s[xx][yy]==‘#‘||vis[xx][yy][1])  continue;
38             vis[xx][yy][1]=1;
39             f.x=xx,f.y=yy,f.flag=1,f.step=e.step+1;
40             p.push(f);
41         }
42     }
43     return -1;
44 }
45 int main()
46 {
47     cin>>h>>w>>d>>r;
48     getchar();
49     for(int i=1;i<=h;i++){
50         for(int j=1;j<=w;j++)
51         scanf("%c",&s[i][j]);
52         getchar();
53     }
54     memset(vis,0,sizeof(vis));
55     cout<<bfs()<<endl;
56 }

 1 #include "iostream"
 2 #include "cstdio"
 3 #include "cstring"
 4 #include "string"
 5 #include "algorithm"
 6 using namespace std;
 7 const int maxn=1e5+10;
 8 long long L;
 9 int n;
10 typedef pair<long long,long long> Node;
11 Node p[maxn];
12 int main()
13 {
14     cin>>L>>n;
15     cout<<(2>>1)<<endl; 
16     for(int i=1;i<=n;i++)
17     cin>>p[i].first>>p[i].second;
18     sort(p+1,p+1+n);
19     long long s=0;
20     for(int i=1;i<=n;i++)
21     s+=p[i].second;
22     s=(s+1)>>1;
23     long long o=0,l=0;
24     int b=0;
25     for(int i=1;i<=n;i++){
26         o+=p[i].second;
27         if(!b&&o>=s) b=1,l=p[i].first;
28     }
29     long long ans=0;
30     for(int i=1;i<=n;i++){
31         if(p[i].first<l) ans+=(l-p[i].first)*(p[i].second);
32         else ans-=(l-p[i].first)*(p[i].second);
33     }
34     cout<<ans<<endl;
35 }