【练习】dp

dp两遍
f[i][j]
数组分段f[i][j]

E. Block Sequence

#include<iostream>
#include<cstring>
using namespace std;
const int N=200010;
int f[N];int a[N];
int n;
int main(){
    int T;
cin>>T;
while(T--){
        cin>>n;
        for(int i=1;i<=n;i++){
            cin>>a[i];
        }

memset(f,0x3f,sizeof(f));
f[0]=0;
for(int i=1;i<=n+1;i++){
    f[i]=min(f[i-1]+1,f[i]);
if(i+a[i]+1<=n+1)
    f[i+a[i]+1]=min(f[i+a[i]+1],f[i]);
    //[i+1,i+a[i]+1]
}
cout<<f[n+1]-1<<endl;
}

}

C1. Magnitude (Easy Version)
最小和最大两个