c语言中将输入的正整数进行逆向输出。
1、do语句结合while语句
#include <stdio.h>
int main(void) { int i; puts("please input an integer."); do { printf("i = "); scanf("%d", &i); if (i <= 0) puts("the range is > 0"); } while (i <= 0); if (i > 0) printf("the reversed: "); while (i > 0) { printf("%d", i % 10); i /= 10; } return 0; }
↓
#include <stdio.h>
int main(void) { int i; puts("please input an integer."); do { printf("i = "); scanf("%d", &i); if (i <= 0) puts("the range is > 0"); } while (i <= 0); int reversed = 0; while (i > 0) { reversed = reversed * 10 + i % 10; i /= 10; } printf("the reversed: %d\n", reversed); return 0; }
2、编写函数, 没有形参的函数
#include <stdio.h>
int func1(void) { int i; puts("please input an integer."); do { printf("i = "); scanf("%d", &i); if (i <= 0) puts("the range is > 0."); } while (i <= 0); return i; } int func2(int x) { int i = 0; while (x > 0) { i = i * 10 + x % 10; x /= 10; } return i; } int main(void) { int x = func1(); printf("the reversed: %d\n", func2(x)); return 0; }