c++计算单利和复利存款金额

//计算单利和复利存款金额

#include

using namespace std;

double simpleinterest(double principal,double interestrate,int year);

double compoundinterest(double principal,double interestrate,int year);

int main()

{

//A的本金

const double daphneprincipal = 100;

//B的本金

double Cleoprincipal = 100;

//A的利率

const double daphneinterestrate = 0.1;

//B的利率

const double Cleointerestrate = 0.05;

int year = 1;

bool flag = true;

while(flag)

{

double daphnemoney = simpleinterest(daphneprincipal,daphneinterestrate,year);

double cleomoney = compoundinterest(Cleoprincipal,Cleointerestrate, year);

if(daphnemoney >= cleomoney)

{

year++;

}

else

{

cout<<"year:"<

cout<<"money:"<

flag = false;

}

}

}

//计算单利模式时总金额

//principal 本金  interestrate 利率  year 年

double simpleinterest(double principal,double interestrate,int year)

{

return principal * (1 + interestrate*year);

}

//计算复利模式时总金额

//principal 本金  interestrate 利率  year 年

//复利利息计算公式(1 + n )^y  n是利率 y是时间（年）

double compoundinterest(double principal,double interestrate,int year)

{

double mutisum = 1;

for(int i = 0; i < year ; i++)

{

mutisum = mutisum*(1 + interestrate);

}

return principal*mutisum;

}