第一次作业（例题）

例 4-12 (1)

/* 源程序:exp6_3.cpp*/# include<stdio.h># include<stdlib.h>void main(){int r;int g;r=rand();printf("Input a number:");scanf("%d",&g);if(g==r)printf("Right!\n");}

 

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例 4-12 (2)

 

/*源程序：exo4_12(2).cpp*/#include<stdio.h>#include<stdlib.h>void main(){int r;int g;r=rand();printf("Input a number:");scanf("%d",&g);if(g==r)printf("Right!\n");elseprintf("The number is:%d,You are wrong!\n",r);}

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例 5-2

/*源程序:exp5_2.cpp*/#include<stdio.h>int main(){ int i=1;  int sum=0;  while(i<=100)  { sum=sum+i;    i++;  }  printf("sum=%d\n",sum);}

 

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例 5-5

/*源程序:exp5_5.cpp*/#include<stdio.h>void main(){ int i;  int sum=0;  for(i=1;i<=100;i++)  {  sum=sum+i*(i+1);  }  printf("1*2+2*3+3*4+...+100*101=%d\n",sum);}

 

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