当我在Dev C ++中运行此程序时，它将执行直到提示输入变量“ C”的整数值。然后，我输入值，整个程序崩溃。没有语法错误；问题是当我不使用IF（条件）语句时运行正常。
[下图显示了我编译并运行程序时的输出的样子。] [1]
// Program to display patterns of numbers according to the input values
#include <stdio.h>
int main()
{
int i, j, in, ni, jn, nj, c;
printf("For the statements for(i=ni;i<=/>=in;i++/--) and\n");
printf("For(j=nj;j<=/>=jn;j++/--),\n");
printf("\nEnter ni: ");
scanf("%d", &ni);
printf("\nEnter in: ");
scanf("%d", &in);
printf("\nEnter nj: ");
scanf("%d", &nj);
printf("\nEnter jn: ");
scanf("%d", &jn);
printf("\nSelect your choice for the type of for loop to be used:\n");
printf("\n01. for(i=ni;i<=in;i++) & for(j=nj;j<=jn;j++)\n");
printf("\n02. for(i=ni;i<=in;i++) & for(j=nj;j<=jn;j--)\n");
printf("\n03. for(i=ni;i<=in;i++) & for(j=nj;j>=jn;j--)\n");
printf("\n04. for(i=ni;i<=in;i++) & for(j=nj;j>=jn;j++)\n");
printf("\n05. for(i=ni;i<=in;i--) & for(j=nj;j<=jn;j++)\n");
printf("\n06. for(i=ni;i<=in;i--) & for(j=nj;j<=jn;j--)\n");
printf("\n07. for(i=ni;i<=in;i--) & for(j=nj;j>=jn;j--)\n");
printf("\n08. for(i=ni;i<=in;i--) & for(j=nj;j>=jn;j++)\n");
printf("\n09. for(i=ni;i>=in;i++) & for(j=nj;j<=jn;j++)\n");
printf("\n10. for(i=ni;i>=in;i++) & for(j=nj;j<=jn;j--)\n");
printf("\n11. for(i=ni;i>=in;i++) & for(j=nj;j>=jn;j--)\n");
printf("\n12. for(i=ni;i>=in;i++) & for(j=nj;j>=jn;j++)\n");
printf("\n13. for(i=ni;i>=in;i--) & for(j=nj;j<=jn;j++)\n");
printf("\n14. for(i=ni;i>=in;i--) & for(j=nj;j<=jn;j--)\n");
printf("\n15. for(i=ni;i>=in;i--) & for(j=nj;j>=jn;j--)\n");
printf("\n16. for(i=ni;i>=in;i--) & for(j=nj;j>=jn;j++)\n");
printf(
"\nInput must be between 1 and 16 inclusive(Including 1 and 16 too)\n");
scanf("%d", &c);
if (c == 1)
{
for (i = ni; i <= in; i++)
{
for (j = nj; j <= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 2)
{
for (i = ni; i <= in; i++)
{
for (j = nj; j <= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 3)
{
for (i = ni; i <= in; i++)
{
for (j = nj; j >= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 4)
{
for (i = ni; i <= in; i++)
{
for (j = nj; j >= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 5)
{
for (i = ni; i <= in; i--)
{
for (j = nj; j <= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 6)
{
for (i = ni; i <= in; i--)
{
for (j = nj; j <= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 7)
{
for (i = ni; i <= in; i--)
{
for (j = nj; j >= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 8)
{
for (i = ni; i <= in; i--)
{
for (j = nj; j >= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c == 9)
{
for (i = ni; i >= in; i++)
{
for (j = nj; j <= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 10)
{
for (i = ni; i >= in; i++)
{
for (j = nj; j <= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 11)
{
for (i = ni; i >= in; i++)
{
for (j = nj; j >= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 12)
{
for (i = ni; i >= in; i++)
{
for (j = nj; j >= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 13)
{
for (i = ni; i >= in; i--)
{
for (j = nj; j <= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 14)
{
for (i = ni; i >= in; i--)
{
for (j = nj; j <= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 15)
{
for (i = ni; i >= in; i--)
{
for (j = nj; j >= jn; j--)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c = 16)
{
for (i = ni; i >= in; i--)
{
for (j = nj; j >= jn; j++)
{
printf("%d", i);
}
printf("\n");
}
}
else if (c < 1 || c > 16)
{
printf("Invalid choice input. Please enter numbers between 1 and 16 only.");
}
return (0);
}
<source>:34:16: warning: format specifies type 'int *' but the argument has type 'int' [-Wformat]
scanf("%d",c);
~~ ^
<source>:134:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=10)
~^~~
<source>:134:18: note: place parentheses around the assignment to silence this warning
else if(c=10)
^
( )
<source>:134:18: note: use '==' to turn this assignment into an equality comparison
else if(c=10)
^
==
<source>:145:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=11)
~^~~
<source>:145:18: note: place parentheses around the assignment to silence this warning
else if(c=11)
^
( )
<source>:145:18: note: use '==' to turn this assignment into an equality comparison
else if(c=11)
^
==
<source>:156:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=12)
~^~~
<source>:156:18: note: place parentheses around the assignment to silence this warning
else if(c=12)
^
( )
<source>:156:18: note: use '==' to turn this assignment into an equality comparison
else if(c=12)
^
==
<source>:167:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=13)
~^~~
<source>:167:18: note: place parentheses around the assignment to silence this warning
else if(c=13)
^
( )
<source>:167:18: note: use '==' to turn this assignment into an equality comparison
else if(c=13)
^
==
<source>:178:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=14)
~^~~
<source>:178:18: note: place parentheses around the assignment to silence this warning
else if(c=14)
^
( )
<source>:178:18: note: use '==' to turn this assignment into an equality comparison
else if(c=14)
^
==
<source>:189:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=15)
~^~~
<source>:189:18: note: place parentheses around the assignment to silence this warning
else if(c=15)
^
( )
<source>:189:18: note: use '==' to turn this assignment into an equality comparison
else if(c=15)
^
==
<source>:200:18: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
else if(c=16)
~^~~
<source>:200:18: note: place parentheses around the assignment to silence this warning
else if(c=16)
^
( )
<source>:200:18: note: use '==' to turn this assignment into an equality comparison
else if(c=16)
^
==
<source>:34:16: warning: variable 'c' is uninitialized when used here [-Wuninitialized]
scanf("%d",c);
^
<source>:5:26: note: initialize the variable 'c' to silence this warning
int i,j,in,ni,jn,nj,c;
^
= 0
9 warnings generated.