41 lines
640 B
C
41 lines
640 B
C
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#include <stdlib.h>
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#include <stdio.h>
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int main(int pn,const char** ps)
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{
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FILE *e,*f;
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int head[3];
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int pos,n,i;
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char buf[4096];
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if (pn<=1)
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{
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printf("usage: %s <input> <output>\n",ps[0]);
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return 1;
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}
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srand((unsigned)time(NULL));
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f = fopen(ps[1],"rb");
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e = fopen(ps[2],"wb+");
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if (!f || !e)
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return 1;
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fseek(f,0,SEEK_END);
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head[0] = 0x44434241;
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head[1] = ftell(f);
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head[2] = pos = rand();
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fwrite(head,1,sizeof(head),e);
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fseek(f,0,SEEK_SET);
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while ((n=fread(buf,1,sizeof(buf),f))>0)
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{
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for (i=0;i<n;++i)
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buf[i] = buf[i] ^ pos++;
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fwrite(buf,1,n,e);
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}
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return 0;
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}
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