[learn C and fly] 3day Chapter 2 program in C language (exercise 2.3 calculate piecewise functions)

practice 1

#include<stdio.h>
int main(){
    int year,month,day;
    scanf("%d-%d-%d",&month,&day,&year);
    printf("%d-%02d-%02d",year,month,day);

    return 0;
}

practice 2

#include <stdio.h>
int main()
{
  double x,y;

  scanf("%lf",&x);
  if(x<=15){y=4.0*x/3.0;}
  else{y=2.5*x-10.5;}
  printf("f(%.2f) = %.2f",x,y);
  return 0;
}

3

#include <stdio.h>
#include<math.h>
int main()
{
    // Input gives two positive integers in sequence in one line money、year And a positive real number rate, Space off 
    int money,year;
    double sum,rate;
    scanf("%d %d %lf",&money,&year,&rate);
    //pow(1+rate,year) intend 1+rate Of year Word power 
    sum=money*pow(1+rate,year);
    
    printf("sum = %0.2f",sum);
    
    return 0;
}

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