《C语言程序设计（Visual C++ 6.0环境）》电子教案：C语言的基本概念

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– C
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C
– 1973 Ritchie kernighan UNIX
– 1989 ANSI/ISO CC89
– 1999 C++ C99
C
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ASCII
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C89 31 C99 5
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Hello World!” C
#include <stdio.h>
int main()
{
printf(“Hello World! \n”);
return 0;
}
printf() stdio.h”
’\n’
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// Get the average value of three floats
#include <stdio.h>
int main()
{
float a,b,c,aver;
printf(“Please input three floats:\n”);
scanf(“%f,%f,%f”,&a,&b,&c);
/* Computing */
aver = (a + b + c) / 3;
printf(“\naverage = %f\n”,aver);
return 0;
}
I/O
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#include <stdio.h>
int xmin(int x,int y)
{
int m; if(x<y) m = x; else m = y; return m;
}
int main()
{
int a,b,a_b_min;
printf(“Please input two integers:\n”);
scanf(“%d %d”,&a,&b);
a_b_min = xmin(a,b);
printf(“\nThe min is %d.\n”,a_b_min);
return 0;}
I/O
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m ain()
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0
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