C :

#include<stdio.h>
#include<stdlib.h>
int main(){
	    double eletric,money;
	scanf("%lf",&eletric);
 
    if(eletric<=150)	
        money=eletric*0.4463;//电量少于150KWh时的电费
    if(eletric>150&&eletric<=400)	
        money=150*0.4463+(eletric-150)*0.4663;//电量多于150KWh，少于400KWh时的电费
    if(eletric>400)		
        money=150*0.4463+250*0.4663+(eletric-400)*0.5663;//电量多于400KWh时的电费
    
    printf("%.1lf",money);//保留小数点1位
    printf("\n");//换行

	return 0;
}

Python :

n = int(input())
if n <= 150:
    a = n * 0.4463
    print(round(a,1))
if n > 150 and n <= 400:
    a = 150 * 0.4463 + (n - 150) * 0.4663
    print(round(a,1))
if n > 400:
    a = 150 * 0.4463 + 250 * 0.4663 + (n - 400) * 0.5663
    print(round(a,1))