C, 53 bytes

int main(a,b){for(;a^'f';a++){printf("%d\n",a-!!a);}}

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43 bytes

k;main(){for(;k^'e';k++)printf("%d ",k);}

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C, 53 bytes

int main(a,b){for(;a^'f';a++){printf("%d\n",a-!!a);}}

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43 42 bytes

(Thanks to Jo King♦)

k;main(){for(;k^'e';)printf("%d ",k++);}

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C, 53 bytes

int main(a,b){for(;a^'f';a++){printf("%d\n",a-!!a);}}

Try it online!

C, 53 bytes

int main(a,b){for(;a^'f';a++){printf("%d\n",a-!!a);}}

Try it online!

43 bytes

k;main(){for(;k^'e';k++)printf("%d ",k);}

Try it online!