c++ decimal point retention

1. Decimal point retention in c++

#include<bits/stdc++>
using namespace std;
int main(){
    
    
 float x=1.2630;
 //保留一位小数
 cout<<fixed<<setprecision(1);
 cout<<x<<endl;
 //保留两位小数
  cout<<fixed<<setprecision(2);
  cout<<x<<endl;
//一次类推.......
}

2. Accumulation between integers with a as the starting point and b as the ending point

#include<bits/stdc++>
using namespace std;
int main(){
    
    
 int a,b,i;
 for(i=a;i<=b,i++){
    
    
	cout<<i;
	}
}