C语言中动态内存分配功能的示例程序
问题
如何使用C语言中的动态内存分配功能显示和计算n个数字的和?
解决方案
以下是C语言程序,用于显示元素并通过使用动态内存分配函数由用户计算n个数字的总和。在这里,我们还尝试减少内存浪费。
示例
#include<stdio.h> #include<stdlib.h> void main(){ //Declaring variables and pointers,sum// int numofe,i,sum=0; int *p; //Reading number of elements from user// printf("输入元素数: "); scanf("%d",&numofe); //Calling malloc() function// p=(int *)malloc(numofe*sizeof(int)); /*Printing O/p - We have to use if statement because we have to check if memory has been successfully allocated/reserved or not*/ if (p==NULL){ printf("Memory not available"); exit(0); } //Printing elements// printf("Enter the elements : \n"); for(i=0;i<numofe;i++){ scanf("%d",p+i); sum=sum+*(p+i); } printf("\nThe sum of elements is %d",sum); free(p);//Erase first 2 memory locations// printf("\nDisplaying the cleared out memory location : \n"); for(i=0;i<numofe;i++){ printf("%d\n",p[i]);//Garbage values will be displayed// } }输出结果
执行以上程序后,将产生以下结果-
Enter the number of elements: 4 Enter the elements: 23 45 67 89 The sum of elements is 224 Displaying the cleared out memory location: 7410816 0 7405904 0