#include
    
     #include 
     
      #include
      
       void fuli(){    double F,P,I;    int M,N;    system("cls");    printf("\t欢迎进入复利计算软件\n");    printf("请输入存入本金:");    scanf("%lf",&P);    printf("请输入年利率:");    scanf("%lf",&I);    printf("请输入存入年限:");    scanf("%d",&N);    printf("请输入年复利次数:");    scanf("%d",&M);    printf("本金\t年利率\t存入年限\t年复利次数\n");    printf("%.2lf\t%.2lf\t%d\t%d",P,I,N,M);    I=pow((1+I/M),M)-1;    F=P*pow((1+I),N);    printf("\n输出复利终值结果：%.2lf\n",F);}void danli(){        double F,P,I;    int N;    system("cls");    printf("\t欢迎进入单利计算软件\n");    printf("请输入存入本金:");    scanf("%lf",&P);    printf("请输入年利率:");    scanf("%lf",&I);    printf("请输入存入年限:");    scanf("%d",&N);    printf("本金\t年利率\t存入年限 \n");    printf("%.2lf\t%.2lf\t%d ",P,I,N);    F=P+P*I*N;    printf("\n输出复利终值结果：%.2lf\n",F);}void benjin(){    double F,P,I;    int M,N;    system("cls");    printf("\t欢迎进入本金计算软件\n");    printf("请输入终值:");    scanf("%lf",&F);    printf("请输入年利率:");    scanf("%lf",&I);    printf("请输入存入年限:");    scanf("%d",&N);    printf("请输入年复利次数:");    scanf("%d",&M);    printf("终值\t年利率\t存入年限\t年复利次数\n");    printf("%.2lf\t%.2lf\t%d\t%d",F,I,N,M);    I=pow((1+I/M),M)-1;    P=F/pow((1+I),N);    printf("\n输出本金结果：%.2lf\n",P);}void nianfen(){    double F,P,I,N;    int M;    system("cls");    printf("\t欢迎进入投资年限计算软件\n");    printf("请输入终值:");    scanf("%lf",&F);    printf("请输入年利率:");    scanf("%lf",&I);    printf("请输入本金:");    scanf("%lf",&P);    printf("请输入年复利次数:");    scanf("%d",&M);    printf("终值\t年利率\t本金\t年复利次数\n");    printf("%.2lf\t%.2lf\t%.2lf\t%d",F,I,P,M);    I=pow((1+I/M),M)-1;    N=log(F/P)/log(1+I);    printf("\n输出投资年限估计：%lf\n",N);}void lilv(){    double F,P,I;    int M,N;    system("cls");    printf("\t欢迎进入投资项目利率计算软件\n");    printf("请输入终值:");    scanf("%lf",&F);    printf("请输入本金:");    scanf("%lf",&P);    printf("请输入存入年限:");    scanf("%d",&N);    printf("请输入年复利次数:");    scanf("%d",&M);    printf("终值\t本金\t存入年限\t年复利次数\n");    printf("%.2lf\t%.2lf\t%d\t%d",F,P,N,M);    I=pow(pow(F/P,1.0/N),1.0/M)*M-M;    printf("\n输出投资项目利率：%lf\n",I);}void dingqi(){    double F,P,I;    int N;    system("cls");    printf("\t欢迎进入定期投资软件\n");    printf("请输入年投入:");    scanf("%lf",&P);    printf("请输入年复合增长率:");    scanf("%lf",&I);    printf("请输入持续投入年数:");    scanf("%d",&N);    printf("年投入\t年复合增长率\t持续投入年数\t\n");    printf("%.2lf\t%.2lf\t%d\t",P,I,N);    F=P*(1+I)*pow((1+I),N-1)/I;    printf("\n输出结果：%.2lf\n",F);}main(){    int i;    printf("\t欢迎进入单复利计算软件3.0\n");    printf("\n1.单利计算");    printf("\n2.复利计算");    printf("\n3.求本金");    printf("\n4.求投资年限");    printf("\n5.求投资项目利率估计");    printf("\n6.定期投资");    printf("\n请输出选择项:");    scanf("%d",&i);    switch(i)    {    case 1:        danli();        break;    case 2:        fuli();        break;    case 3:        benjin();        break;    case 4:        nianfen();        break;    case 5:        lilv();        break;    case 6:        dingqi();        break;    default:        return 0;    }}