1.unsigned short i,j;for(i=0, j=2; i!=j; i+=5, j+=7){}2.unsigned short i,j;for(i=3,j=7;i!=j;i+=3,j+=7){}#include<stdio.h>int main(){ unsigned char i=7; int j=0; for(;i>0;i-=3) { ++j; } printf("%d\n",j); return 0;}原文：http://www.cnblogs.com/fenglongyu/p/7635984.html