C语言实例（适用于初学者）

//1.判断闰年的函数 int run(int year) { if(year%4==0&&year%100!=0||year%400==0) return 1; else return 0; } //2.每月的天数 int getday(int year,int mon) { int days; switch(mon) { case 1: case 3: case 5: case 7: case 8: case 10: case 12:days=31;break; case 4: case 6: case 9: case 11:days=30;break; case 2: if(run(year)==1) days=29; else days=28; break; } return days; } //3.计算闰年个数 int getruns(int year) { int i,runs=0; for(i=1900;i<year;i++) { if(run(i)==1) runs++; } return runs; } //4.计算整年天数 int getzheng(int year) { int zheng; zheng=365*(year-1900)+getruns(year); return zheng; } //5.计算不整年天数 int getbuzh(int year,int mon) { int bzh; switch(mon) { case 1:bzh=1;break; case 2:bzh=31+1;break; case 3:bzh=31+28+1;break; case 4:bzh=31*2+28+1;break; case 5:bzh=31*2+30+28+1;break; case 6:bzh=31*3+30+28+1;break; case 7:bzh=31*3+30*2+28+1;break; case 8:bzh=31*4+30*2+28+1;break; case 9:bzh=31*5+30*2+28+1;break; case 10:bzh=31*5+30*3+28+1;break; case 11:bzh=31*6+30*3+28+1;break; case 12:bzh=31*6+30*4+28+1;break; } if(run(year)==1) { if(mon>=3) bzh+=1; } return bzh; } //6.计算总天数 int getzong(int year,int mon) { int zong; zong=getzheng(year)+getbuzh(year,mon); return zong; } //7.计算星期 int getwk(int year,int mon) { int wk; wk=getzong(year,mon)%7; return wk; } //8.打印字符 void print_char(int x,char ch) { int i; for(i=1;i<=x;i++) { printf("%c",ch); } } //9.打印结果 void print_mon(int year,int mon) { int i,m; int wk=getwk(year,mon); int days=getday(year,mon); printf("\t\t\t%d年%d月\n",year,mon); print_char(50,'='); printf("\n"); printf("星期日\t星期一\t星期二\t星期三\t星期四\t星期五\t星期六\n"); print_char(wk,'\t'); m=wk; for(i=1;i<=days;i++) { printf("%d\t",i); m++; if(m%7==0) printf("\n"); } printf("\n"); } //10.打印年历? //11.定义一个函数判断成绩是否及格 int check(float s) { if(s>=60) return 1; else return 0; }