5-8

#include
     
      float cash;int main(void){    int choice;    float value;    void income(float number),expend(float number);    cash=0;    printf("Enter operate choice(0--end,1--income,2--expend):");    scanf("%d",&choice);    while(choice!=0){        if(choice==1||choice==2){            printf("Enter cash value:");            scanf("%f",&value);            if(choice==1)                income(value);            else                expend(value);            printf("current cash:%.2f\n",cash);        }        printf("Enter operate choice(0--end,1--income,2--expend):");        scanf("%d",&choice);    }    return 0;}void income(float number){    cash=cash+number;}void expend(float number){    cash=cash-number;}
     

 

5-9

#include
     
      double fact_s(int n);int main(void){    int i,n;    printf("Input n:");    scanf("%d",&n);    for(i=1;i<=n;i++)        printf("%3d!=%.0f\n",i,fact_s(i));    return 0;}double fact_s(int n){    static double f=1;    f=f*n;    return(f);}